Add share option to main menu (but not recognized, yet).
Share icons
Added a basic share action (but doesn't generate a URL fragment for the
filters, yet).
Restore basic linking functionality again.  We lose the ability to
select text -- need to figure out how to make both work.
Got clicking on links and text selection working together.
Remove obsolete intents from manifest.
Replace URLSpan in text view when the link should be handled internally
in Sloop.
Linkify in the XML instead of Java code.
Switch to a regular expression for links that Sloop can handle.