Added "DELETED" state to RequirementStatus

-- added DELETED state

This seems necessary based off of some documentation on user stories
found on VersionOne. I will inquire about this further with Marty
Javadoc and uniqueID field to Epic

--  Made javadoc for Attachment, Note, Epic and Task
--  Add uniqueID field to Epic
--  Additional comments/explanations/notes
Development of uniqueID for Epic

--  Comments for various instances of uniqueID in the epic class
--  Getters and setters for uniqueID
--  Javadocs for the Epic class
Resolved conflicts with workflow

Merge branch 'dev-model' of https://github.com/gsisko/wpi-suite-tng into dev-model

--  Fixed conflicts between my commits and Mike's

Conflicts:
	RequirementManager/src/edu/wpi/cs/wpisuitetng/modules/requirementmanager/model/Attachment.java
	RequirementManager/src/edu/wpi/cs/wpisuitetng/modules/requirementmanager/models/Epic.java
	RequirementManager/src/edu/wpi/cs/wpisuitetng/modules/requirementmanager/models/Task.java