chore(gruntfile): Add html files to grunt watch

When changing html template, grunt watch must be triggered.
feat(momentjs): Add angular-moment dependency

This adds angular-moment and momentJS as dependencies.

angular-moment is a wrapper momentJS wrapper for angularJS.

This allow handling timezone, formatting, week numbering and calendars based on locale.

dateFunctions service and ganttDate filter have been dropped.

Closes #124
Closes #158
Closes #97