adding a message attribute to the browse widget

* extend browse widget with a message attribute. If blank then import as
original. Otherwise, dispatch the given message with selected files
Docs updates
Release note update
Merge pull request #999 from Eucaly/browse-widget

adding a message attribute to the browse widget
Coding style cleanups
Docs for update to browse widget
Filename typo
Readme update
Move release note and update HelloThere

Preparing for release of 5.1.3
Update release instructions
Version number update for 5.1.3
Preparing for 5.1.4
Update WidgetMessage_ tm-add-tag.tid
Docs typos
Merge pull request #1001 from gernert/patch-4

Update WidgetMessage_ tm-add-tag.tid
Improved export icon