* refactor: add libtransmission-app
* refactor: add libtransmission-app/display-modes.h
* refactor: use app::SortMode, app:ShowMode in Qt client
* feat: add to_variant(), to_value() in serializer
* refactor: use app::SortMode in GTK client
* refactor: use app::ShowMode in GTK client
* refactor: make naming consistent with libtransmission-app
There're places where manual intervention is still required as uncrustify
is not ideal (unfortunately), but at least one may rely on it to do the
right thing most of the time (e.g. when sending in a patch).
The style itself is quite different from what we had before but making it
uniform across all the codebase is the key. I also hope that it'll make the
code more readable (YMMV) and less sensitive to further changes.
Split FileTree.{h,cc} and FilterBar.{h,cc} files so that each class
is in its own file.
This breaks translations (some classes got renamed => context changed),
to be fixed by next commit (along with Tx sync).
