distribute_license: added class to copy license files
distribute_license: added class to copy license files

* This class can be used to copy license files from package
  sources into the deploy directory so they can be distributed.
* By default it searches the top-level source directory for
  files matching COPYING* or LICENSE*
* Search depth and pattern can be modified using the
  LICENSE_SEARCH_DEPTH and LICENSE_FILES variables
  respectively.

Signed-off-by: Chase Maupin <874d7d4fa211492c1868f6a91442712d37040f21@ti.com>
Signed-off-by: Denys Dmytriyenko <e7d361c7f6c045f0c4fa54d2afc4a237f30bc767@denix.org>

mrchapp/arago-da830,mrchapp/arago-da830,mrchapp/arago-da830