Updated Qt Creator application logos

The leaf does not have a white border, anymore. The .ico and
.icns files now have a shadow.

Task-number: QTCREATORBUG-13359
Change-Id: Iebdc6aefb36592333f1d76cd28a407a121318bb6
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>
A shell script for creating application icons

This script creates several application icon files by using
Inkscape to rasterize .svg items to .png, adding shadows via
imagemagick, creating .ico files via imagemagick and .icns
files via iconutil (OSX only).

Also, this change tweaks applicationicons.svg so that the
shadows won't be cut off.

Change-Id: Ie8adf37d775fa5ea02329451932956f760c17620
Reviewed-by: Alessandro Portale <alessandro.portale@digia.com>