Merge pull request #1 from VDVsx/master

Add methods to encode and decode mail passwords
Merge pull request #2 from VDVsx/master

 Reset folders model when account key is set
Merge pull request #3 from VDVsx/master

Add StandardFoldersRetrieved role to account list model.
[nemo-qml-plugin-email] Add enablers to test account configuration.

Add StandardFoldersRetrieved role to account list model.
Add accountId property and improve configuration testing.
Add methods to encode and decode mail passwords.
[nemo-qml-plugin-email] Remove obsolete htmlfield code.