Lua Extensions: implement fake "require"
Lua Extensions: implement fake "require"

As the "descriptor" function is called with absolutely no libraries
loaded, even the built-in "require" function is not present at scan
time.
This closes #3453.

Note: this is a bit of a hack, but I prefer not to load any libs when
scanning the available extensions

Remove some useless debug, too

jomanmuk/vlc-2.2,krichter722/vlc,xkfz007/vlc,vlc-mirror/vlc,jomanmuk/vlc-2.2,vlc-mirror/vlc,jomanmuk/vlc-2.2,vlc-mirror/vlc,krichter722/vlc,jomanmuk/vlc-2.1,xkfz007/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.1,krichter722/vlc,jomanmuk/vlc-2.1,xkfz007/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,xkfz007/vlc,xkfz007/vlc,vlc-mirror/vlc,vlc-mirror/vlc-2.1,vlc-mirror/vlc,shyamalschandra/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.2,krichter722/vlc,vlc-mirror/vlc-2.1,jomanmuk/vlc-2.1,jomanmuk/vlc-2.2,vlc-mirror/vlc-2.1,krichter722/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc-2.1,shyamalschandra/vlc,vlc-mirror/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc-2.1,krichter722/vlc,xkfz007/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc-2.1,shyamalschandra/vlc,krichter722/vlc,vlc-mirror/vlc,xkfz007/vlc,vlc-mirror/vlc-2.1