Fixed the absolute paths in the desktop file

The application icons now install into the system icon theme. This also
results in the system always picking the best available icon to display.

To make installing simpler (and to make the names more consistent) the
icon files were moved into the folders of their resolution.

Fixes #383

(cherry picked from commit 9aeac457bb7f98f5d3987164a74b8445dd9977c7)
Removed inconsistent zoom factors in tileset view

I prefer if there's a single set of predictable zoom factors for both
the map and the tileset view.
Install the automappingconverter application
Flare export plugin: Remove checks for certain layers being there

The flare engine evolved and supports 2 more layers optionally.
The three layers which were checked being there, should still be there,
but are not necessary. Also I cannot recall any errors due to missing
or miss spelled layers during flare development, so I think we do not
need this check for flare.

The check for these three layers unintentionally hindered other projects
using this format, which is another reason to drop the check.

(cherry picked from commit 58a3d5f57a82d41671cad9aa89825b38ddc49072)
Merge branch '0.9'

Conflicts:
	docs/tiled.desktop
	src/tiled/images/16x16/application-x-tiled.png
	src/tiled/images/16x16/tiled.png
	src/tiled/images/32x32/application-x-tiled.png
	src/tiled/images/32x32/tiled.png
	src/tiled/images/scalable/application-x-tiled.svg
	src/tiled/images/scalable/tiled.svg
	src/tiled/images/tiled-icon-16.png
	src/tiled/images/tiled-icon-32.png
	src/tiled/images/tiled-icon.svg
	src/tiled/tiled.pro