Reacquire GIL to create the python string object

Thanks to Dieter Koessl for reporting.
https://sourceforge.net/p/npppythonscript/discussion/1188885/thread/566ac7bf/#ca2a
Version 1.0.5
Fix parameters for SCN_MARGINCLICK
Fix parameters for SCN_NEEDSHOWN
Fix params for SCN_URIDROPPED
Fix params for SCN_INDICATORCLICK and SCN_INDICATORRELEASE
Fix text parameter for unknown event

This shouldn't occur, but if scintilla is updated in N++ before Python Script then it's possible.  This will stop a crash in case text is NULL.