v2.1.5

Changelog

78f2d60 Add test for content of generated files
be88ff2 Doesn't fail if can't upload coveralls.
483a4e5 Merge pull request #32 from rekby-forks/fix-return-without-expected
8bae907 Merge pull request #33 from rekby-forks/fix-coverall
12b7496 Merge pull request #34 from ailurarctos/go-generate-comment-convention
6263ba6 Use the go:generate comment convention
9aa01d2 Work with default return without expected params