Added basic VoiceOver support to DTAttributedTextContentView.
Modified demo text view controller to hide non-visible content views to avoid conflicts with VoiceOver.
Invalidate accessibility elements when explicitly setting the layout frame.
Created view proxy for accessible attachments as subviews.
Merge upstream.
Re-added accessibility files to project.  Documented DTAccessibilityViewProxy
Documented DTAccessibilityElement.  Modified the designated initializer.
Documented layout frame accessibility element generator.
Added some comments.  Implemented hash/isEqual in view proxy.
Disabled stripping on non-Foundation DTCoreText lib
Update DTFoundation to 1.4.2
implemented weak ref support (if deployment target allows it) #311
Merge branch 'od/issue_311' into develop
Removed DT_ADD_FONT_ON_ATTACHMENTS, there should always be a font added, even for attachments. #463
Updated isTrailing to work correctly for RTL
do not subtract trailing whitespace width for RTL text.
Change glyph run building to use first glyph position as offset. Fixes #444
Test HTML for #444
Merge branch 'od/issue_444' into develop
Added unit tests for #462 and #447