Updated to data format revision 3

Revision 3 introduces support for storing usernames
Added support for storing usernames

Implements the database format v3 and adds a username prompt as well as
display of usernames. The entire feature can be disabled.
Updated tests for username support
Improved test coverage of username-specific features
Fixed handling of just pressing enter on the username prompt
Mention the support for storing usernames in the manpage
Don't exit after v2->v3 upgrades
Added tests for data v2 to v3 upgrades
Clear the current status message before upgrading
Return the upgraded data from upgradeDataV2toCurrent
Re-ordering tests
Added a test for upgrades when using git
Merge branch 'master' into usernameStorage
If the password isn't changed, don't re-encrypt it
Grant a -0.5 bonus to entries that have a username
Don't output a "username" header if we have no usernames

Also changes the "no-usernames" header to match the "usernames" one more closely
Output the username while the password is being decrypted
Fixed the test plan
Corrected clibpardMode parameter
Verify that gpgDecryptString receives a string