Move Debug Functionality in MainForm

Moves the click methods related to debugging and testing out of button
click methods and into the Menu Strip item, under the "Debug" section.
Removes the buttons from the form.
Add CaptionTextBox

Adds CaptionTextBox, which is meant for marking captions with emotions.
Add CaptionView_SelectionChanged Event Handler

Adds an event handler to mainform that changes the Caption in
CaptionTextBox. Adds a more complex setter to CaptionTextBox.Caption
so that the Text gets updated as well.
Add Length property to CaptionWord

Adds the Length Property. Adds SelectionChanged event handler to
CaptionTextBox.
Add CaptionWordList class

Adds CaptionWordList, which is to be designed for manipulation of
CaptionWords either individually or as a whole string.
Add CaptionWordListUnitTest
Add FeedTest Functionality

Adds FeedTest Functionality and code modifications to pass the test.
Add TextOutputTest

Adds a test that ensures the Text output from a CaptionWordList is the
same as its input.
Remove CaptionData

Removes CaptionData, a class that has been replaced by CaptionView.
Update Caption class

The Caption class now uses a CaptionWordList instead of a generic List
object. Caption.FeedWordList(String line) and Caption.WordListText are
removed as they are implemented in CaptionWordList.
Add CaptionWordList.AsString property

Adds the AsString property to caption list, which when set provides the
same functionality as Feed(string line), and when get, the same
functionality as GetAsString().