In an effort to make GDScript a little faster replace the double
switch() with a computed goto on compilers that set __GNUC__. For
compilers that don't support computed goto it will fall back to regular
switch/case statements.
In addition disable using boolean values in a mathematical context. Now
boolean values can only be compared with other booleans. Booleans will
also no longer be coerced to integers.
This PR replaces #11308 and fixes#11291