Fix part of #110.

Fix #110 (;b and ;t don't respond to 'activate'. Behavior spec'd in
:help is unclear).

I've fixed the inverted ;b/;t behaviour (the bug), closed the ticket,
and added 'activate' support as a TODO.

vimperator/TODO

@@ -33,6 +33,7 @@ FEATURES:
 9 adaptive timeout for auto-completions, :set completions can be updated more often than
   :open foo
 9 use the storage module for autocommands
+8 support 'activate' in buffer.followLink?
 8 add support for filename special characters such as %
 8 :redir and 'verbosefile'
 8 middleclick in content == p, and if command line is open, paste there the clipboard buffer