Log Message:
Updated p5-libwww to 6.19.

6.19    2017-02-14
    - Call HTTP::Status constant functions without & (GH#110)
    - Make bin scripts use LWP's version and not maintain their own (PR #54)
    - Fix bug triggered in some cases of auth challenges not having a viable
      protocol (PR#111)
    - Remove usage of the 'vars' pragma (GH#113)