kpatch: install to initrd and load patch modules on boot

When doing "kpatch install", copy the patch modules to the initrd and
install a dracut hook which calls "kpatch apply --all".
kpatch: load core module in kpatch apply
kpatch: print status messages

Print status messages for load/unload/install/uninstall to give the user
a better idea of what's going on.
Merge pull request #106 from jpoimboe/kpatch-install-initrd

kpatch: install patch modules to initrd