fixed typos

"Verschlüsselungscode Anforderung" -> "Verschlüsselungscode-Anforderung"
"Kennowrtsatz" -> "Kennwortsatz"
FreeBSD compatibility.
Fixed the path in shell executable when DESTDIR isn't empty.
[NEW FEATURE] Implemented the indicator in tray icon that there are unread messages.
Fixed grammar: 'Waiting on' -> 'Waiting for'
Fixed grammar: 'Waiting on' -> 'Waiting for'
Merge pull request #591 from Atheros1/master

Added translation to UI; also updated all .ts files
Merge pull request #571 from hanswolff/patch-1

fixed typos
Merge pull request #574 from yurivict/compatibility_FreeBSD

FreeBSD compatibility
Merge pull request #575 from yurivict/install_issues

Fixed the path in shell executable when DESTDIR isn't empty
Merge pull request #576 from yurivict/tray_inbox_unread_indicator

[NEW FEATURE] Implemented the indicator in tray icon that there are unread messages
resolve merge conflict