mint-arena: Fix not showing notify text at intermission

Show chat messages while at intermission. Disabled by accident.
mint-arena: Fix SkipRestOfLine going past end of string

If string data starts with a 0 (string terminator), don't skip over it at p++.

Fixed loading OpenArena's ayumi skin. Ends with "tag_head",
CG_RegisterSkin tries to skip line.
mint-arena: Fix showing players on podiums at end of single player levels
mint-arena: Use Xbox 360 like virtual gamepad like SDL2

j_*_axis cvars were removed. Now axiis are remapped to virtual keys and run binds.
+moveup, +forward, etc in binds will use axis data if 'key' event is an axis and analog is enable.

Add support for using 'A' button to skip cinematics.
Added support for using 'B' button to pop menu.
Improve support for using dpad and left stick (even with analog enabled!) in menu.

(No improvements were made to the Team Arena UI.)
mint-arena: Add syscalls for cgame to get/set joyevent remaps

This should allow adding support for configuring joystick remaps in the UI.
mint-arena: Move getting keys for current joy events into cgame
mint-arena: Fix trap_JoyEventToString
mint-arena: Use multiple joyevents structs for axis and hat in cgame events

These will be needed for sending events to UI code for joy remap.
mint-arena: Add in_joystickDebug to show joy event presses

Makes it easier to manually remap joy to keys using 'joyremap <event> <key>'.

Also compare keys against -1 not 0 to see if set.
mint-arena: Ignore duplicate mouse events

Fixes using keyboard and gameplay to navigate in windowed mode
(which updates mouse x/y each frame).
mint-arena: Don't allow selecting banner in player settings

Causes no visual effect resulting in 'missing' cursor.
Problem for keyboard and gamepads.
mint-arena: Update keycodes.h
Merge remote-tracking branch 'mint-arena/master'