Add message arguement to /query

Closes #757
Improve text repositioning when searchbar string is modified.
Add fullscreen to to view menu
Replace more GDK_* with GDK_KEY
Make manual reposition after unfullscreen Windows only
Add /d2Zi+ switch for better debug symbols
Fix messages on networks that have chantypes the same as nick prefixes

Closes #763
First round of using GTK accessor functions

This is the first step to build with GSEAL_ENABLE
setup.c uses a deprecated fontchooser,
chanview-tabs.c didn't like the conversion, and
I am waiting to do some work on xtext.c before
converting it.
Fix warning
Add screenshot to appdata file
Strip trailing space from CAP REQ

Mentioned in #770
Fix url detection of channel with nick prefix

Closes #769
Only underline the channel part if nick prefix
Fix /cycle command

- Uses the correct channelkey when called from another tab
- Allows it to be used from any tab in the same server
- Verifies it's a channel you are in
Revert menu.c @ ae04663aa9

This caused a few bugs such as improperly setting away/back
and redrawing the channel tree when the menu is opened.
Update help messages for userlist buttons and user popups
typo..
Fix tab completion with utf8 completion char

Closes #738
Split long messages at spaces
Remove hextray