fix csrc definition injection fail to some source code
fix csrc error without no additional header file path
fix ffi.import that causing error for typedef no named struct
prepare for releasing 0.2.0-2 (hotfix for 0.2.0)
Merge pull request #7 from umegaya/umegaya/hotfix/0.2.0

Umegaya/hotfix/0.2.0 travis build passes.