Safecheck atcommand

-Add restriction for atcommand to prevent possible mapcrash from script
or console usage while waiting full portability.
-Upd athena-start for new default binname.
-Remove petstat as it was similar to getpetinfo and copy only missing
attribute level atribute into getpetinfo.
-Merge useatcmd and atcommand as they shared quite the same code, also
properly differenciate useatcmd from normal player call.
--Upd script-documentation about it thx Euphy.
Merge branch 'master' of https://github.com/rathena/rathena