ocf-distro: Improve robustness and specificity (#1558)

• ocf-distro: Add SUSE check to get_os_ver()
• ocf-distro: Reduce code duplication, functionalize version-get
• ocf-distro: Add is_debian_based() and is_suse_based() functions
• azure-lb: Use is_suse_based() when setting OCF_RESKEY_nc_default
• apache: Use is_suse_based() and is_debian_based()
• ocf-distro: Try os-release first to get release ID
• ocf-distro: Make uname -s the final fallback for release ID
• ocf-distro: Normalize OS release IDs in get_release_id()
• ocf-distro: Functionalize getting OS from legacy source
• ocf-distro: Try os-release first to get OS version
• ocf-distro: Functionalize getting OS version from legacy source
• ocf-distro: Functionalize processing of retrieved values

Signed-off-by: Reid Wahl <nrwahl@protonmail.com>