Added IterationEstimate class to calculate the total estimate of all the requirments in an iteration
Minor filtering for ID only implemented. GUI in place for future changes
Added a check in the validate method of the RequirmentsModelValidator
Makes sure the iteration being assaigned is not over yet
Updated validators for requirement fields and added call to validate function.
Also improved logic for setting which fields are editable at each stage.

Contributors:
	David Modica
fix #38
fix #38
fix #39
change estimated and actual effort to int
Merge branch 'dev-feature-filters' into dev
Added filters capable of filtering based on any one column, added ability for future modifications via listener file, commented well
Major Refactoring in GUI, added and removed scrollbars where needed,
made notes panel fit screen, still need to fix individual notes, crt req
doesn't break when resized ever now
Made some minor changes to the note panel. It now fills up the area, but wont shrink anymore
Fixed comments in actions, controllers, and requirements management to refer to requirements, not defects
Added headers and fixed comments in the controllers module
Added headers and documentation to entity managers and gui
Added headers in listeners and models
Last round of header fixes
Forgot one, now all the files have headers.
Fixed issue where you could not assaign an iteration to a requirement if the last day of the iteratoin was today
notes more condensed, filter removed