Merge branch 'development' for 0.2.0

- adds (some) endpoint tests
- adds endpoints:
    withdraw_from_label
    withdraw_from_address
    withdraw_from_labels
    withdraw_from_addresses
    withdraw_from_users
- make clear that license is MIT
- fix README.md file length
open 0.2.1
Remove redundant version

Parse package.json inside the library to reduce metadata redundancy
format README.md