Implemented changes for translatewiki

Moved to Json i18n files
Use image instead of picture for better consistency
Changed filename, filetypes to file name, file types
Improved messages better punctuation
Removed unused message
Removed deprecated file
Changed message key

Change-Id: I34e6d509ea1b67c7ad2eb17489dc1be597092701
Merge "Implemented changes for translatewiki"