v0.2.0

• Added a -v/--version flag.
• Added a plugin system.

ThriftRW now provides a plugin system to allow customizing code generation.
Initially, only the generated code for service declarations is
customizable. Check the documentation for more details.

• Breaking: Fixed a bug where all-caps attributes that are not known
  abbreviations were changed to PascalCase.
• Breaking: The String() method for enum types now returns the name
  of the item as specified in the Thrift file.