Clean up pool handling during patch application, mostly for readability.
Clean up pool handling during patch application, mostly for readability.

* subversion/libsvn_client/patch.c
  (init_patch_target): Take two pools, a result pool and a scratch pool,
   and use them accordingly.
  (copy_lines_to_target): If we create an iterpool, we might as well use it.
  (read_lines_from_target): Fix typo in docstring, and put pool arguments
   in the conventional order.
  (apply_one_patch): Pass two pools to init_patch_target. Since all allocations
   done here are scratch allocations, we can't push the result/scratch pool
   pattern higher up the call stack.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion