* added help for timesheet duration form field - fixes#138
* added label option to link to manual chapter
* created docu chapter "timesheet" and added duration mode docu
* allow field and form option "documentation" to link to chapters in the documentation
- fixed group by for mysql mode
- only user can edit own prefs
- updated installation README
- pagerfanta shows less links
- improved manual tab
- moved user profile link to pref tabs
- added menu links to top navbar
- moved page actions to breadcrumb position
- integrated daterangepicker and improved toolbar forms
- bugfix for time rounding
