attempt to fix yvt/openspades#243
Merge pull request #255 from barzoj/master

attempt to fix yvt/openspades#243
edited to suit cmake
script for downloading DevPak
renamed make.sh to converticons.sh
edited `make install` behaviour; also some cpack tweaks
added OpenSpades_Resources target
Added option -DOPENSPADES_RESOURCES
updated .travis.yml to make this option working from now on
Merge pull request #257 from noway421/cmakelists_revision

`make && make install` improves on linux
added code for setting window icon
now using FileManager::OpenForReading
includes
added icon.inc
icon from .rodata
added icon to splash screen
added icon to screenhelper
Splitted downloading resources and icon generating to 2 targets