[INSTALLER] added numpy version check to linux installer

    pyopenms install fails for systems with numpy 1.6.0, so
    I added numpy version check.
    Further renamed install_linux.sh -> install_emzed2.sh
    updated installation instruction on website.
[FEATURE] print path of db file when loading pubchem
[FIX] patched spyderlib.requirements.check_qt()

    check_qt() failed for Qt >= 4.10.0 due to string comparision.
    had to patch this locally as we stick to spyderlib 2.1.3
    this bug is fixed in  spyderlib >= 2.2.0
[RELEASE] v 2.2.1