replaces sed with elisp in re-tag action
* mu4e: replaces sed with elisp in re-tag action
mu4e: fixes new elisp re-tag implementation for forward slashes
* mu4e: uses correct helper function naming conventions.
* mu4e: Whoops, uses actual correct helper function naming conventions (~ instead of -)
* mu4e: retagging: +/- are only special at the beginning of terms (thanks to seanfarley)
Merge pull request #158 from pygatea/master

* re-implements "retagging" action in elisp to get around sed version inconsistencies between platforms
* cosmetics
* mu: allow for searching the mailing-list field (list:/v:)
* configure.ac: fix gtk2/3 test
* configure.ac: remove gtk+2 support (only gtk+3)
* minor
* mug.c: remove gtk2 compat code
* toys/mug: mu-msg-view: add separator
* toys/mug: mu-msg-header-view: use GtkGrid instead of GtkTable
* toys/mug: remove gtk2 compat code, small cleanups
* mu4e: update documentation
* mu4e: don't use beginning-of-buffer non-interactively (fixes compilation warning)
* small updates for mu.1 manpage
Set mu4e-headers-view-win to nil when closing message view.