Add build script for generating Code::Blocks project on Windows host.

Close #644.

cmake_codeblocks.bat

@@ -0,0 +1,23 @@
+::
+:: Copyright (c) 2008-2014 the Urho3D project.
+::
+:: Permission is hereby granted, free of charge, to any person obtaining a copy
+:: of this software and associated documentation files (the "Software"), to deal
+:: in the Software without restriction, including without limitation the rights
+:: to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+:: copies of the Software, and to permit persons to whom the Software is
+:: furnished to do so, subject to the following conditions:
+::
+:: The above copyright notice and this permission notice shall be included in
+:: all copies or substantial portions of the Software.
+::
+:: THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+:: IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+:: FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+:: AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+:: LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+:: OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+:: THE SOFTWARE.
+::
+
+@%~dp0\cmake_generic.bat %* -G "CodeBlocks - MinGW Makefiles"