Retreive booked minutes by start and end date

We generalize the getBookedMinutes method and use a generic start and
end date. We use this method in minutesBookedAction.
Make the end date in the model api exclusive

We choosed to use exclusive end dates therefore I changed the model API
to use exclusive end dates.
Deprecate legacy jsonMonthListAction() in favor of monthListAction()
Use start and end dates in monthJsonList
Remove unused code and refactor gteRecords

We don't need openPerid & co in the frontend therefore we don't
need the code to determine if a period is open or not. We can
reduce getRecords to dates and a sum that can be easily expressed
in SQL.
Use timecard model in SummaryBlock
Use start and end dates for timeard calls in frontend
If no start date is given use last contracts start date
Reuse fetchByUserAndPeriod
Javascript
Use a table to display summaries
Remove unused function
End date is always today
Merge branch 'next' into PTC-59

Conflicts:
	phprojekt/application/Timecard/Controllers/IndexController.php
	phprojekt/application/Timecard/Models/Timecard.php
	phprojekt/htdocs/phpr/BookingList/SummaryBlock.js
	phprojekt/htdocs/phpr/models/Timecard.js
Use today as default endday

The current calculations for the current month use the whole month it's
calculation period. This results in a "hours to work" to be calculated
for the full month. In fact the user is interested how much he has to
work till today. So we change the default end date to today.
Use static method call
Fix indention
Use getEffectiveUser() instead of getRealUser()

We should always user getEffectiveUser() instead of getRealUser() to make
sure our backend is proxy mode compatible.
$start and $end are optional parameters in fetchByUserAndPeriod
Readd project filter but make it optional