Aiotx

- AioTxETHClient covered by tests and ready to be used
- nonce is now optional param to give users enter in manually for sending transactions faster
- get_contract_decimals function added for EVMClient, now you can get decimals for contracts

- Added tests for send and send_token function, they was renamed and changed, getting pending for nonce now

- Function for getting current gas price is added and to_wai/from_wai functions are attached to EVM client now

- block/transactions monitoring added, examples of usage added, tx input decoding added

- EVM client base logic added (get_balance, send tokens)
- tests added

- EVM networks wallet generation logic added