Merge pull request #1 from sota0805/master

Add: cal_exporter.gemspec: homepage data
Add: README: description
Merge branch 'develop' of github.com:sota0805/cal_exporter into develop

* 'develop' of github.com:sota0805/cal_exporter:
  Add: cal_exporter.gemspec: homepage data
Merge pull request #2 from sota0805/develop

Develop