API guide updates
Add Content Item Etensions Support and RIN Integration
Add Support for Themed-Collections
Merge pull request #835 from javierluraschi/CollectionColors

Add Support for Themes
Merge pull request #845 from javierluraschi/ExtensionsAndRIN

Add Content Item Etensions Support and RIN Integration
removed bookends
Merge pull request #855 from willum070/docs

API guide updates
bugfix 774:
now timeline and exhibit dates in datepickers are displayed correctly
+refactored unit-tests
Merge pull request #856 from GiorgiyLutidze/bugfix744_2

Bugfix774