Show announcements in timetable views

Blocked by AlekSIS!184 (merged)

Closes #63 (closed)

changed milestone to %2.0a2

added part::frontend type::feature workflow::blocked labels

mentioned in merge request AlekSIS!184 (merged)

added 2 commits

• 49cb122f - Rename queryset methods for announcements
• 1ed1dd51 - Use API provided through ExtensibleModel to extend announcement query set

Compare with previous version

resolved all threads

@nik It's ready to merge.

resolved all threads

added 1 commit

• edfd5296 - Move extensions for announcement model to model_extensions.py

Compare with previous version

resolved all threads

merged

mentioned in commit 30e640c9