Log Message:

Update to 0.50

  pkg_grep_summary:
     - fix for case insensitive search (pkg_digger_backend)
     - new artificial fields were added: PKGPANA and PKGPABA,
       see the manual page for details

  pkg_bin_summary:
    - new artificial field PLIST was added.

  pkg_uniq_sumary:
    - new option -n was added

  pkg_summary2deps:
    - new option -a was added for outputting all matched dependencies
      separated by `|' symbol, not only the first one.
    - new options -N and -P were added
    - new option -X was added
    - if multiple packages satisfy the condition, the package with highest
      version is selected unless -a option was specified.
    - another format for missed alternative dependencies.
      Now they are written as altdep1|altdep2|...|altdepN

  pkg_lint_summary:
    - option -d: non-zero status if problems were detected

  New tool pkg_summary2leaves was added.

  pkg_cmp_summary:
    - long options were removed
    - option -2 was added
    - option -u was added for showing information about whether
       the package from summary1 is installed by user or as a dependency.

  pkg_summary2deps:
    - workaround for bad patterns like p5-Digest<=1.16nb*
      found perl binary

  pkg_refresh_summary:
    - reimplemented using latest version of pkg_grep_summary.
      This removes about 50 lines of code

  minor fixes and clean-ups