Similar to c4cfeb6bbf8d, avoid crashes due to bad references.

Make sure argc is always valid when QCoreApplication access it, by keeping
it as a reference to argc from main.
Merge pull request #243 from MJDSys/argc_fix

Similar to c4cfeb6bbf8d, avoid crashes due to bad references.
Append failsafe session

Failsafe is always the last session to be added to the model, this
makes it the default session only if there are no other sessions.

Closes #235
Exit loop as soon as last session is selected

No need to continue any further when the last index is set.
Move and update the INSTALL file.
Merge pull request #244 from jleclanche/master

Add a basic INSTALL file
Update man pages

Fixes #231
Update changelog
Add contributor

Add Matthew Dawson <matthew@mjdsystems.ca>
Bump version to 0.9.0
Move X11 specific code from Display to DisplayServer

A step forward for a display server agnostic sddm.
With Wayland support coming soon we want display server specific code
not scattered all over the place.
Set HAVE_SYSTEMD when building with systemd support
Log display server command line

For debugging purpose.
Turn DisplayServer into an abstract class

Move Xorg specific code to XorgDisplayServer, this will allow us to
support multiple display server.
Update change log
One CMakeLists.txt file for each subdirectory

It's easier to work with separate CMakeLists.txt files, one for each
subdirectory.
Remove Arch Linux packages

No point in having those here, Jerome is maintaining them
on AUR.
Remove Qt 4 support

The time has come, SDDM is finally a Qt 5 only software.

[ChangeLog][General] SDDM now requires Qt 5.
Flush log file

Writes to the log file immediately.

[ChangeLog][General] Flush any buffered data to the log file,
this writes immediately all the log messages.

Issue: #182
Remove trailing whitespace