Sync English PO files with the latest code for Havana-3

Closes-Bug: #1221539

This commit updates English PO files only which requires for
translation. Other languages are not updated since they will
be update by importing translations from Transifex.

Change-Id: I126291ca5eb7c607b86446c2351062ce87600bbb
Remove test string from translation files

Closes-Bug: #1221123

Removing unnecessary translation strings reduces translation work.
String Freeze is enabled so this patch also update en PO files.

Change-Id: Ie69c8d0b990e53678262457094852b1ef4966b8b