doc: move translations kcm to plasma-workspace as well
at time of moving, index.docbook was at commit,
c1b9e8003febb1da46b110ff7a92e5b4e036b732
and plasma-desktop head was at,
6eb2d544c767d49b9dfc3dc8f5f1b5b26912f8ca
Removed in commit,
ced62362743e113813e5e8d9cc292c88be413875
CCMAIL: Burkhard Lück <lueck@hube-lueck.de>