And drop associated _pkg.dev remnants (refs. #307).
Original `dev` branch had two separate packages for public and private keys,
but those are so intertwined (`TestHelper` subpackage is a proof) that it's
better unite them and all associated code (like WIF and NEP-2) in one
package. This patch also:
* creates internal `keytestcases` package to share things with wallet (maybe
it'll be changed in some future)
* ports some tests from `dev`
* ports Verify() method for public key from `dev`
* expands TestPrivateKey() with public key check
Simplifies a lot of code and removes some duplication. Unfortunately I had to
move test_util random functions in same commit to avoid cycle
dependencies. One of these random functions was also used in core/transaction
testing, to simplify things I've just dropped it there and used a static
string (which is nice to have for a test anyway).
There is still sha256 left in wallet (but it needs to pass Hash structure into
the signing function).
* small fixes
* gofmt
* fix in raw tx build
* fixes after review
* balance getter interface
* moved address and signature calculation to public key
* errors handling
* PublicKey() returns PublicKey instead of bytes slice
* fixes after review
* fixes after review
* public key creation from asn1 serialized key
* small fixes
* gofmt
* fix in raw tx build
* fixes after review
* balance getter interface
* moved address and signature calculation to public key
* errors handling
* PublicKey() returns PublicKey instead of bytes slice
* fixes after review
* fixes after review
* added account_state + changed ECPoint to PublicKey
* account state persist
* in depth test for existing accounts.
* implemented GetTransaction.
* added enrollment TX
* added persist of accounts and unspent coins
* bumped version -> 0.32.0
