updated documentation

Change-Id: I710dd1df715c58b6383ae06dc737eac462d11de6
CustomLayerWindow no longer uses hard-coded list of plotters.
Renamed AutoResizingTextArea -> Paragraph, set more common defaults, and
improved whitespace trimming behavior.
AlertTextBox now selects all text when it opens.
Added help text to SessionStateEditor's linking controls.
Code & GUI cleanup.

Change-Id: I9f30a3a48bd589b74242423b187afa508439aed0
control panels for object editors are now remembered & reused.

Change-Id: I08d8de9021cb7892adf201800342710389805624
added additional checks

Change-Id: Ie0562bd12398311e5166235c6fc6ddf6798e3701
AddDataSourcePanel now closes when new data source is added.

Change-Id: Ib799da069afcf5dee37bfb3b0d0698528c3e2d17
"Nested unlink" button is now disabled when it can't be used.

Change-Id: Ieb1cd14d5c03237a566e58d9cfd4a2fd6da071ac
escape key no longer closes EditDataSourcePanel

Change-Id: I5f731896a7c4daafe7ed918ad9f52fa3d129031d
Clicking "Cancel" after "Add Marker" now removes the marker.

Change-Id: Iefd06043af3cde5e10d4719c23dc200866a0b9b7
organizing imports

Change-Id: Ie6d4df91f21c4033cc4b393eb73519ee6591a128
fixed Paragraph size calculation / display bug
LocalAsyncService now calls fault responders for pending async calls
when it fails to connect.
Improved default DraggablePanel.controlPanel.title
fixed Paragraph display bugs
Removed option to edit equation text (it wasn't saved in session state
anyway).
Fixed equation whitespace trimming display bug.
increased height of multi-line edit
WeaveAPI.getRegisteredImplementationDisplayName() now calls lang(), so
there is no need to remember to call lang() when passing display name to
WeaveAPI.registerImplementation().

Change-Id: I35c8bc688db1ae912c9070a1d089c0e77180408d
improved data source editing interface.

Change-Id: I42e79d0e95771371ce9d407b0a6dc7b2944bb3fe
fix null pointer error
fixed bug where _internalObject wasn't getting cleared in dispose()
Overhauled add/edit data source panels.
ILinkableObjectEditor now has a function to check for pending changes.
DynamicColumnEditor now allows changing the active data source.
DynamicColumnEditor now refreshes active category when hierarchy
changes.
Numerous bug fixes related to GUI-linked objects becoming disposed.
UIUtils.pad() now does more useful stuff.