Clean up dependencies

Upgrade iotex-address and go-pkgs

claim reward caller

• add claim reward api
• allow user to set nonce on actions

fix exec bug

make version 2 (#60)

* make version 2

* v2

fix send action bug

fix gas price is not set (#58)

* fix gas price is not set

* comment

New API interface

Merge pull request #57 from iotexproject/yutongp-patch-1

Update README.md

first release

v1.0.0

Use existing private key interface to create account (#55)