add const qualifier

Change-Id: I88d61668b465e505cfa245dd17893828aaaecaa8
detect if Standard is only library to *save*

as opposed to only library at all

Change-Id: I23bebfe7d156e1f4a60bc5f265a3cf9d295f3e4a
fdo#52076 remove Library dir when no library

when saving to same storage (in place)
we already did that when empty "Standard" was the only library,
but not when there was no library...
Cannot get through that state in through UI, but possible through scripting.

Change-Id: I0f1129e034ac31b3eaf6bd388a03aee5aae5b87e
janitorial: add const, factorise constant

Change-Id: Ifdaff62611452ce1e39604bd751168fe3e68d865
fdo#52076 unittest

Change-Id: Iae10f9728db4c90c4a55ad692b32cddeb7adc48a