Make the title field output from keepassx2pass.py more command line frie...

As Password Store uses KeepassX title fields for file names, the KeepassX titles often make very poor file names.  My own KeepassX database was a mess after export to Password store.  Command line completion of password titles was challenging due to the need to escape so many characters in the title.  

My goal in this pull request is to remove characters that require escaping while attempting to preserve as much meaning in the filename as possible.  These changes are now made to the KeepassX title before it is used as a file password store filename:

* Spaces between words in file names are replaced with camelCasing.
* The characters \ | ( ) are each replaced with a hyphen.
* Trailing hypens are removed.
* @ is replaced with "At"
* ' is removed

Philip