Changes

Remove OMShellLib. (#12281)

- The issue started with OMShell reporting
    `qt.svg: Cannot open file ':/Resources/omshell-large.svg', because: No such file or directory`
    at startup on Linux.

    The qrc file was added in the lib sources instead of the executable
    sources. This works fine on Windows but not on Linux.

    As it turns out there is no need to have OMShellLib anyway. It is now
    removed and the sources for it are moved to OMShell.