Updated API reference documentation.

Reset build options to not build XML (default).
Merge and final polishing
Merge pull request #523 from alterm4nn/NewUIFormFix

UI improvements: header forms
Merge pull request #522 from willum070/docs

Updated API reference documentation.
Fixed post build script to accept filepaths with whitespaces.
[BugFix] Bug #180 - Preserve content item order in exhibits
[HotFix] Show icons in authoring forms