v0.3.1

v0.3.1 was rebuild by angular-cli because v0.2.3 has problem that "JIT Compiler Unavailable" on Angular 14.

I confirm to work v0.3.1 on Angular 14. I guess also work on Angular 12 & 13.
But older than Angular 12 are not supported.
(Maybe v0.2.3 work on older Angular.)

* v0.3.0 was abandoned due to npm publish problem.

v0.2.3

v0.2.3 was changed followings:

• Removed some file such as index.ts, test/ in npm package.
  (It occured compile error on newer TypeScript.)
• Add type to some callbacks.
• Change build target to ES2015.