Argument handling

• sgs_ArgErrorExt - emit an argument type mismatch error with additional formatting options
• sgs_ArgError - emit an argument type mismatch error
• sgs_FuncArgError - emit an argument type mismatch error (alias for states where this variable is hidden)
• sgs_MethodArgError - emit an argument type mismatch error (alias for states where this variable is NOT hidden)
• sgs_LoadArgsExtVA - parse the stack as an argument list with additional options (for custom wrapper functions)
• sgs_LoadArgsExt - parse the stack as an argument list with additional options
• sgs_LoadArgs - parse the stack as an argument list
• sgs_ParseMethod - the this object variable handling function, using the macro is preferred to this
• SGS_PARSE_METHOD - automagically handle a this object variable regardless of the way its passed
• sgs_Method - unhide the first variable on stack if there is a hidden this variable
• sgs_HideThis - hide the first variable on stack if the stack already doesn't contain a hidden this variable
• sgs_ForceHideThis - hide the first variable even if it wasn't previously hidden before unhiding
• sgs_ArgCheck_Object - argument parsing function for parsing any objects
• sgs_ObjectArg - returns the additional integer argument for object interface function calls