Unlock approved months, updated Custom-Portal, improved work-contract calculation

Features

• Change browser title to use Kimai instead of Kimai Time-Tracking
• Re-add username column in Excel spreadsheet
• Allow line breaks in custom Javascript
• Translations update
• Fix error on empty code in Kiosk login form
• Fix identifier already defined in search

Work Contract

• Do not include any future times in work contract calculation
• Unlock approved months (with new permission unlock_times_contract)
• Validate entire lock period for pending absences

Translations

• Fix switching between single-line and multi-line entries
• Fix saving multi-line entries

Customer Portal

• Fix design for empty project list
• Fix too many timesheets shown for customer portals with empty project list