releasme & plasma 5.10

[Harald Sitter]

Ahoy hoy,

I am currently in the progress of landing fairly invasive changes to
how documentation is handled in releaseme as previously mentioned in
'cmake magic for documentation' thread after Jonathan was nice enough
to get rid of some excess code in the plasma repos that was blocking
this.

As a result of this Plasma 5.10.5 needs to be created from the
'Plasma/5.10' branch of releaseme. NOT master!

For 5.11 master is good to use again.

(reason is that 5.10.5 will still have the code which releaseme
supports but kdoctools does not, so releasing 5.10.5 with releaseme
from master would change cmake behavior in a point release which is
undesirable)

HS