gpaste-client: track connection errors

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>

Conflicts:
	src/gpaste/gpaste.c
fix README

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
clipboards-manager: use Xfixes

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>

Conflicts:
	libgpaste/core/gpaste-clipboards-manager.c
update TODO

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
Merge branch '3.0'

* 3.0:
  update TODO
  clipboards-manager: use Xfixes
  fix README
  gpaste-client: track connection errors

Conflicts:
	README.md
	TODO
	libgpaste/core/gpaste-clipboards-manager.c
	libgpaste/settings/ui/gpaste-settings-ui-stack.c
	src/gpaste/gpaste.c