LU-6245 libcfs: create userland and kernel string operations

Additonal string handling and NID string parsing code are both
used by kernel space and user land. This prevents us from
moving forward for cleaning up the userland and kernel space
headers. With the code duplicated for both environments we
can then clean up the headers independently. Since NID string
handling is only done for LNET we move it there.

Signed-off-by: James Simmons <uja.ornl@gmail.com>
Change-Id: I5fccdae61322d0bace7094a36d2e551d719c4982
Reviewed-on: http://review.whamcloud.com/13835
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>