Intent with tab, normalize commands

- indent with tabs (more configurable)
- normalized some comments
- removed 3 useless lines ([calendar.js#L293](https://github.com/Serhioromano/bootstrap-calendar/blob/cf3ffa616cdc36e5191f459a57a75309f03776cd/js/calendar.js#L293))

PS: to not view space-only changes in this PR you can visit
https://github.com/Serhioromano/bootstrap-calendar/pull/73/files?w=1
instead of
https://github.com/Serhioromano/bootstrap-calendar/pull/73/files