Add the ability to mod mouse cursors

This supports cursors for:
* Hovering over map events and loot
* Hovering over living enemies
* Hovering over NPCs

As well as a normal cursor.
Allow setting offsets for modded mouse cursors
Reload icons after recreating render context
Merge pull request #979 from dorkster/fixes

Reload icons after recreating render context
Merge pull request #977 from dorkster/mouse_cursor

Context sensitive mouse cursor graphics
Reinitialize CursorManager when changing mods or resolution
Merge pull request #980 from dorkster/fixes

Reinitialize CursorManager when changing mods or resolution
Add a configuration option to use only hardware mouse cursor

Fixes #981

The setting is found on the Interface tab of the config menu and is off
by default.
Merge pull request #982 from dorkster/mouse_cursor

Add a configuration option to use only hardware mouse cursor
Updated the Galician (gl) translation
Merge pull request #987 from hean01/master

Make indentation script work on header files.
Merge pull request #983 from Gallaecio/gl

Updated the Galician (gl) translation
Move screen-edge alignment to util function
Add configuration file for title screen layout
Suppress error message when engine/mouse_cursor.txt can't be opened

Modded mouse cursors is an optional feature, so we don't need to display
a message if we don't have it.
Merge pull request #990 from dorkster/fixes

Suppress error message when engine/mouse_cursor.txt can't be opened
Move title screen music to engine/default_music.txt
Merge pull request #992 from dorkster/title_screen

Move title screen configuration to text files
Remove x_origin and y_origin from WidgetLabel

Fixes #991
Merge pull request #993 from dorkster/label

Remove x_origin and y_origin from WidgetLabel