erp5_base: Include symbols on generatePassword

   Include some symbols to allow this script to be more complaint with erp5_authentication_policy, and more common practices of password settings.

   I explicity didnt include string.ponctuation because it introduces some unusual charts that are not commonly found on passwords like brackets, braces, angle brackets...

bt5/erp5_base/SkinTemplateItem/portal_skins/erp5_base/Person_generatePassword.py

-return ''.join(random.SystemRandom().sample(string.ascii_letters + string.digits, length))
+return ''.join(random.SystemRandom().sample(string.ascii_letters + string.digits + '_-.$%:;!', length))