uisupport: Forcefully disable horizontal scrollbar in BufferView
Qt 5.10.1 severly broke QHeaderView and by extension, QTreeView,
resulting in a horizontal scrollbar being shown. In order to avoid
making this issue too obvious for people using that version of Qt
(including the builds currently generated by our CI), force the
scrollbar to be hidden in BufferView.
The contents can still be scrolled sideways e.g. with horizontal
mouse wheel emulation, but that should not hit many users in
practice.
Earlier or later versions of Qt seem to not suffer from that issue,
but always hiding the scrollbar doesn't hurt either way.
(cherry picked from commit dd27cd1f84ecceb5fb287894373d4cb42131a03f)
cmake: Add exception handling support to MSVC compile flags
Since STL types may throw, MSVC needs to get told to support
exceptions by specifying the /EHsc flag. Otherwise, it warns about
the lack thereof, even though Quassel itself does not use nor handle
exceptions.
Closes GH-350.
(cherry picked from commit 7a8ea3eee1dcff4eaa5398d1cf5739fa32eccd9e)
Don't terminate the core due to backend issues while setting up
If the storage backend selected by the user during core setup cannot
be initialized, the problem shall be communicated to the client and
the user can start over; the core shall not exit in this case.
Ensure that failure to initialize the selected backend only terminates
the core if it's not being setup.
