Update README

description for alix6-bugfixes
add ifmodule for mod_rewrite

Signed-off-by: Sweil <mail@sweil.de>
fixed cimg link

Signed-off-by: Sweil <mail@sweil.de>
Merge branch 'alix6_neu' of github.com:Sweil/Frogsystem-2 into alix6-bugfixes
fixed wrong lang-text references

Signed-off-by: Sweil <mail@sweil.de>
Merge branch 'alix6-bugfixes' of github.com:Sweil/Frogsystem-2 into alix6-bugfixes