Added Support to CORE-1307(Require Page Start and Page End Parameters in get collection API for PDF resources).
Merge remote-tracking branch 'gooru/master'

Conflicts:
	gooru-
core/src/main/java/org/ednovo/gooru/core/constant/ConstantProperties.java
Added Support to Jira Task CORE-1331(Send Email Invite for Open classes).
Merge remote-tracking branch 'gooru/master'
Excluded Resource_info object from CollectionItemFields.
Merge pull request #386 from saravanab/master

Added Support to Jira Task CORE-1331(Send Email Invite for Open classes)