Issues fixed:
* Additional rule validations.
* Rewrote recurrence logic.
* Additional unit tests, especially from the examples in the RFC.
* The date format "YmdThis" results into an incorrect date for the
"UNTIL" parameter. The literal "T" should be escaped, and a literal
"Z" is also needed at the end of the format string to indicate UTC.
* Implemented handling of negative modifier values for BYxxx rules.
* Implemented handling of BYWEEKNO, BYYEARDAY, BYSETPOS, BYHOUR,
BYMINUTE, BYSECOND rules.
If there are multiple, non-repeating events with the same module name,
instance and event type. The most specific event or the event with the
highest priority will be shown.
The ordering of event priorities:
User override events > Group override events > Course events.
If there are no user override events and there are multiple group
overrides for an event, then the one with the highest priority will be
shown.
* New priority column in order to enable the rendering of a single,
relevant calendar event for a module that has user/group overrides.
* Insert refresh_mod_calendar_events_task record to task_adhoc
table to upgrade existing calendar events for mod plugins via cron
after upgrade process.
The events list is now a list of cards with headers.
Spacing and layout is now done with bootstrap utility classes.
The existing classes were kept - and the styles for bootstrapbase are not changed much.
Also calendar colours can be overridden from a preset.
Fix I edit profile steps
Apply fixed header in css
Remove transitions from menus for behat
Be more specific about some "I follow" steps
Navigation path changes
"Current course" node removed from nav tree
Adapt tests because there are no default blocks
Force some space between action menu items
1. getMock()
2. setExpectedException()
3. checkForUnintentionallyCoveredCode renamed to beStrictAboutCoversAnnotation
4. beStrictAboutTestSize renamed to enforceTimeLimit
5. UnitTestCase class is now fully removed.
recentupcoming option is always available everytime calendar export
is called, rest week and month is optionally shown and may not be
visible. So use recentupcoming event option and export calendar for test
component, filearea and itemid are now optional parameters.
In some contexts those parameteres are not necessary because is not
required to do a file rewrite via file_rewrite_pluginfile_urls
