Log Message:
Update graphics/leptonica to 1.74.1

1.74.1  4 Jan 17
- Configuration changes to support the patch number in the
  version (major.minor.patch).
- Removed all remaining pixDisplayWrite() calls in prog/.
- Cleaned up and/or promoted about 15 programs to full regression
  tests.  There are now 95 tests in the regression set.
- Over half the initial coverity scan warnings have been removed.

1.74.0 10 Dec 16
- Leptonica development was moved to github.  The master is at:
  github.com/danbloomberg/leptonica
- Egor Pugin is the maintainer of the site.
- A very large number of changes have been made.  Some of them follow;
- details can be found in the git commit messages.
- Static makefiles modified to work with gnu*9 and c*9.
- Modify SET macros to work on windows.
- New modes for RGB --> gray conversion.
- New functions added for displaying a pix from a pixa.
- Split out sort/hash/set/map functions for dna, sarray and pta.
- More robust horizontal deskew on multi-column page images.
- Improve webpio_reg test.
- Remove X11 display for gplot; it is no longer supported.
- Remove most sleep calls, which were put in for gplot; no longer needed.
- Removed use of gthumb in library.
- Removed use of pixDisplayWrite() in the library; still in some progs.
- Improved test for endianness in makefile.static; no longer requires
  any local files or building and running a program.
- Modified all files for doxygen output (spearheaded by Jurgen Buchmuller)
- Improved plotting of the boxes in a boxa.
- Replaced the slow point hash function with a simple fast one.
- Added pam (4 component) format writing to pnmio.c (Jurgen Buchmuller)
- Improved rendering of pixa in side/by/sides.
- Better utilities for pixa and pixacomp.
- Add read/write serialization functions from/to memory for all
  the major data structures that do not already have them.
- More serialized boot recognizers stored as self-generating code.
- Cleaned up generating an adapted recognizer from the boot recognizer.
- Simplified temp file naming; removed most instances of named
  temp files from non-debug code; use tmpfile() and a wrapper
  l_makeTempFilename().
- Simplify and streamline multipage tiff reading (Jeff Breidenbach).
- Improvement of Otsu thresholding.
- Recognize outstanding contributors to leptonica over the years.
- New gif mem read/write interface that avoids writing a temp file,
  contributed by Tobias Peirick.
- Use double arrays (dna) instead of float (numa) for set ops.
- Enrolled in coverity scan to find potential bugs (Stefan Weil
  managed it). Fixed about 200 of them, mostly potential memory
  leaks from early function exit.
- Cleanup of gray quantization functions and tests.
- Refactored connectivity-conserving operations, to make them more useful.
- Provided methods for measuring and regularizing the width of strokes.
- Removed viewfiles.c from library; code is now in prog htmlviewer.c.
- Better debugging in page segmentation (pageseg.c)
- Deprecated the pixDisplayWrite*() debugging methods.
- Added about 15 regression tests to the framework in alltests_reg.c
- Final mods for compatibility with tesseract 4.00.