Merge pull request #14 from zpbx/dev

Rename project from `action.js` to `action`.
Update doc.
Update README.md
Tiny optimization.
Add return value for `.trigger()` API.
Tiny optimization.
Merge pull request #15 from zpbx/dev

Add return value for `.trigger()` API.
Merge branch 'master' into doc

.
Add source files of documentation, resolve #13.
Merge pull request #16 from zpbx/dev

Add source files of documentation, resolve #13.
Merge branch 'master' into doc

Conflicts:
	doc/api.zh.md
Update doc.
Update doc.