rteval: add the /proc/cmdline to rteval report

Creates a new class cmdlineInfo which is added to the report

example of the output:

 Cmdline:        BOOT_IMAGE=/vmlinuz-3.10.0-663.el7.x86_64
root=/dev/mapper/rhel_dell--pem710--02-root ro crashkernel=auto
rd.lvm.lv=rhel_dell-pem710-02/root rd.lvm.lv=rhel_dell-pem710-02/swap
console=ttyS0,115200n81 isolcpus=3

Signed-off-by: John Kacur <jkacur@redhat.com>

cmdline

Signed-off-by: John Kacur <jkacur@redhat.com>