Fixes some bugs and added database name in top pulley menu

- Bug fixed which lead to wrong behaviour for verify password field on edit entry page (this fixes #36)
- Bug fixed when hitting enter on password field in create new database dialog closes the Create dialog (this fixes #35)
- The database name will be shown now in top menu on open database page where the user inputs the master password for the database. Thus the user knows actually which database he is going to open
- The database name is also shown on groups and entries page in the top menu