Merge pull request #1018 from annando/master

Solved install issues, support for predefined preview picture in page info function
Fixed two typos in strings.php and BBCode.md
Merge pull request #1022 from AlfredSK/master

Fixed two typos in strings.php and BBCode.md
make translation of addons work again
Merge pull request #1023 from tobiasd/fixaddontrans

make translation of addons work again
Merge remote-tracking branch 'upstream/master'
Vier: Preview picture in admin settings is now smaller