*: add more package-specific documentation

For the most important packages at least.

pkg/compiler/doc.go

@@ -0,0 +1,4 @@
+/*
+Package compiler implements Go to NEF smart contract compiler.
+*/
+package compiler

pkg/config/doc.go

@@ -0,0 +1,4 @@
+/*
+Package config contains NeoGo node configuration definition.
+*/
+package config

pkg/config/netmode/doc.go

@@ -0,0 +1,4 @@
+/*
+Package netmode contains well-known network magic numbers.
+*/
+package netmode

pkg/consensus/doc.go

@@ -0,0 +1,7 @@
+/*
+Package consensus contains Neo consensus node implementation.
+
+It uses external dBFT library for the core algorithm and basically joins this
+library with Neo node internals implemented in NeoGo.
+*/
+package consensus

pkg/core/block/doc.go

@@ -0,0 +1,6 @@
+/*
+Package block contains Neo block definition.
+
+This is one of the core structures of Neo blockchain.
+*/
+package block

pkg/core/interop/doc.go

@@ -0,0 +1,7 @@
+/*
+Package interop contains implementations of Neo interop functions.
+
+This is not the package you use from smart contracts, refer to pkg/interop
+for that.
+*/
+package interop

pkg/core/native/doc.go

@@ -0,0 +1,4 @@
+/*
+Package native contains Neo native contracts.
+*/
+package native

pkg/core/transaction/doc.go

@@ -0,0 +1,6 @@
+/*
+Package transaction contains Neo transaction definition.
+
+This is one of the core structures of Neo blockchain.
+*/
+package transaction

pkg/crypto/doc.go

@@ -0,0 +1,6 @@
+/*
+Package crypto contains implementation of crypto functions used by Neo.
+
+This package itself just has some useful interfaces.
+*/
+package crypto

pkg/crypto/hash/doc.go

@@ -0,0 +1,6 @@
+/*
+Package hash contains wrappers for Neo hashing algorithms.
+
+It also implements Merkle tree.
+*/
+package hash

pkg/crypto/keys/doc.go

@@ -0,0 +1,4 @@
+/*
+Package keys wraps public/private keys and implements NEP-2 and WIF.
+*/
+package keys

pkg/encoding/address/doc.go

@@ -0,0 +1,4 @@
+/*
+Package address implements conversion of script hash to/from Neo address.
+*/
+package address

pkg/encoding/bigint/doc.go

@@ -0,0 +1,4 @@
+/*
+Package bigint implements Neo-specific big.Int (de)serialization to/from []byte.
+*/
+package bigint

pkg/encoding/fixedn/doc.go

@@ -0,0 +1,4 @@
+/*
+Package fixedn implements fixed point integers with arbitrary precision.
+*/
+package fixedn

pkg/interop/math/math.go

@@ -1,3 +1,6 @@
+/*
+Package math provides access to useful numeric functions available in Neo VM.
+*/
 package math
 
 import "github.com/nspcc-dev/neo-go/pkg/interop/neogointernal"

pkg/interop/native/crypto/crypto.go

@@ -1,3 +1,7 @@
+/*
+Package crypto provides interface to CryptoLib native contract.
+It implements some cryptographic functions.
+*/
 package crypto
 
 import (

pkg/interop/native/gas/gas.go

@@ -1,3 +1,7 @@
+/*
+Package gas provides interface to GasToken native contract.
+It implements regular NEP-17 functions for GAS token.
+*/
 package gas
 
 import (

pkg/interop/native/ledger/ledger.go

@@ -1,3 +1,7 @@
+/*
+Package ledger provides interface to LedgerContract native contract.
+It allows to access ledger contents like transactions and blocks.
+*/
 package ledger
 
 import (

pkg/interop/native/management/management.go

@@ -1,3 +1,7 @@
+/*
+Package management provides interface to ContractManagement native contract.
+It allows to get/deploy/update contracts as well as get/set deployment fee.
+*/
 package management
 
 import (

pkg/interop/native/nameservice/name_service.go

@@ -1,3 +1,7 @@
+/*
+Package nameservice provides interface to NameService native contract.
+It's a NEP-11 contract implementing a domain name service.
+*/
 package nameservice
 
 import (

pkg/interop/native/neo/neo.go

@@ -1,3 +1,9 @@
+/*
+Package neo provides interface to NeoToken native contract.
+NEO token is special, it's not just a regular NEP-17 contract, it also
+provides access to chain-specific settings and implements commmittee
+voting system.
+*/
 package neo
 
 import (

pkg/interop/native/notary/notary.go

@@ -1,3 +1,8 @@
+/*
+Package notary provides interface to Notary native contract.
+This contract is a NeoGo extension and is not available on regular Neo
+networks. To use it you need to have this extension enabled on the network.
+*/
 package notary
 
 import (

pkg/interop/native/oracle/oracle.go

@@ -1,3 +1,8 @@
+/*
+Package oracle provides interface to OracleContract native contract.
+Oracles allow you to get external (non-blockchain) data using HTTPS or NeoFS
+protocols.
+*/
 package oracle
 
 import (

pkg/interop/native/policy/policy.go

@@ -1,3 +1,7 @@
+/*
+Package policy provides interface to PolicyContract native contract.
+This contract holds various network-wide settings.
+*/
 package policy
 
 import (

pkg/interop/native/roles/roles.go

@@ -1,3 +1,8 @@
+/*
+Package roles provides interface to RoleManagement native contract.
+Role management contract is used by committee to designate some nodes as
+providing some service on the network.
+*/
 package roles
 
 import (
@@ -15,6 +20,7 @@ type Role byte
 const (
 	StateValidator Role = 4
 	Oracle         Role = 8
+	// P2PNotary is an extension of Neo protocol available on specifically configured NeoGo networks.
 	P2PNotary Role = 128
 )
 

pkg/interop/native/std/std.go

@@ -1,3 +1,7 @@
+/*
+Package std provides interface to StdLib native contract.
+It implements various useful conversion functions.
+*/
 package std
 
 import (

pkg/interop/neogointernal/doc.go

@@ -0,0 +1,5 @@
+/*
+Package neogointernal contains definitions of compiler intrinsics.
+It's not intended to be used directly by smart contracts.
+*/
+package neogointernal