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"
"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