Fixes globalvar variable access in scripts

This change makes it so that any variable that is user-defined global
will remove any dot access generated during parsing (including scripts.)
Proper globalvar support

Handles globalvars in scripts by determining whether variable access is
local or global.
Hotfix to prevent local var errors

Related to changes from "Proper globalvar support"
Fix for SFML and sound_add().
Merge pull request #845 from sorlok/sfml_fix

Fix for SFML and sound_add().
Disabled make_directory; it is still used internally (and is platform-dependent), but the option in the dialog box is now ignored.
Change function signature on Linux to match Windows/OSX.
Merge pull request #848 from sorlok/xlib_mouse_fix

Change function signature on Linux to match Windows/OSX.
Merge pull request #844 from sorlok/makedir_hide

Disabled make_directory
Merge pull request #842 from RobertBColton/master

Touch extension and callbacks *DO NOT MERGE*
"ambi" keyword optimization

Increase length of original "amb" keyword to say "ambi" for an O(1)
replace later on.
Merge pull request #840 from Heathtech/master

Resolves #822 globalvar variable access in scripts
Implements directory_delete
Tested on XLIB and Win32