Merge pull request #269 from akhileshdarjee/master

[fix] [minor] fixes for dirty()
[minor] change filename to unicode after os.walk and os.listdir
[minor] fixes in get_base_path
[minor] import cstr
[minor] [fix] POP3Mailbox use ssl
[minor] [fix] default conf.py
[minor] [fix] render grid only if it is visiable
[minor] [fix] when making control, use form's perm
[minor] [fix] url fix in editor webnotes/erpnext#934
[minor] [fix] ignore permission check while removing file, if the referred document does not exist
[fix] [minor] attachment related fixes