Removed unnecessary 'Hello world' contracts
Added required key size and prefix
Modified Put and Get contracts so that they take a key as a parameter
Added test for invalid key case
Modified existing tests
Signed-off-by: Lebedeva Ekaterina <ekaterina.lebedeva@yadro.com>
Tried to implement PutNumber and GetNumber funcs based on contracts in frostfsid_contract.go
Added just one test for now, it's not failing
Signed-off-by: Lebedeva Ekaterina <ekaterina.lebedeva@yadro.com>