Update installation command

Merge pull request #17 from k-yomo/fix-output-bug

Fix trying to create empty dir when only file name is set for the output

Merge pull request #14 from k-yomo/fix-naming-conflict

Fix naming conflict between variable name and package name

Merge pull request #10 from k-yomo/fix-missing-package-name

Fix import bug happened when the package name is same as th target package

Tweak receiver name

Fix too many change logs at release

Fix bug that Build() does not reset builder's build count used for ma…

…pping EachParam()

Create directories if the parent directories of output path not found

Fix bug that struct is not imported correctly when file generate anot…

…her directory

Fix error to find go.mod if targetDir is '.'