Log Message:
Updated ImageMagick to 7.0.7.21.

2018-01-06  7.0.7-21 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.0-21, GIT revision 22168:a91afc45b:20180106.

2018-01-06  7.0.7-21 Dirk Lemstra <dirk@lem.....org>
  * Fix some enum values in the OpenCL code.

2018-01-06  7.0.7-20 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-20, GIT revision 22161:33a04d3e5:20180105.

2018-01-05  7.0.7-20 Cristy  <quetzlzacatenango@image...>
  * Fixed numerous memory leaks (reference
    https://github.com/ImageMagick/ImageMagick/issues).

2018-01-01  7.0.7-19 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-19, GIT revision 22133:977fe08bf:20180101.

2017-12-29  7.0.7-19 Cristy  <quetzlzacatenango@image...>
  * Check for webpmux library version 0.4.4 (reference
    https://github.com/ImageMagick/ImageMagick/issues/896).

2017-12-26  7.0.7-18 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-18, GIT revision 22096:ad4bdeb40:20171228.

2017-12-28  7.0.7-18 Cristy  <quetzlzacatenango@image...>
  * Fix error reading from pipe under Windows (reference
    https://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=33288).

2017-12-26  7.0.7-17 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-17, GIT revision 22093:9caea323b:20171227.

2017-12-26  7.0.7-17 Cristy  <quetzlzacatenango@image...>
  * Fix heap use after free error (reference
    https://github.com/ImageMagick/ImageMagick/issues/918).

2017-12-24  7.0.7-16 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-16, GIT revision 22038:e55dc7626:20171225.

2017-12-18  7.0.7-16 Cristy  <quetzlzacatenango@image...>
  * Fix error reading multi-layer XCF image file.
  * Fix possible stack overflow in WEBP reader (reference
    https://github.com/ImageMagick/ImageMagick/issues/907)
  * Fixed numerous memory leaks (reference
    https://github.com/ImageMagick/ImageMagick/issues).

2017-12-16  7.0.7-15 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-15, GIT revision 21924:30cb31746:20171216.

2017-12-08  7.0.7-15 Cristy  <quetzlzacatenango@image...>
  * Overall standard deviation is the average of each pixel channel (reference
    https://www.imagemagick.org/discourse-server/viewforum.php?f=3).
  * Update to the latest ImageMagick documentation.

2017-12-05  7.0.7-14 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-14, GIT revision 21855:dc73b2aba:20171205.

2017-11-30  7.0.7-14 Cristy  <quetzlzacatenango@image...>
  * Support Stereo composite operator.
  * Fix build failure with --without-modules (reference
    https://github.com/ImageMagick/ImageMagick/issues/890).

2017-11-30  7.0.7-13 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-13, GIT revision 21823:72cb0fd0c:20171130.

2017-11-30  7.0.7-13 Cristy  <quetzlzacatenango@image...>
  * Fix build failure with libraw 0.14.8 (reference
    https://github.com/ImageMagick/ImageMagick/issues/888).

2017-11-29  7.0.7-12 Cristy  <quetzlzacatenango@image...>
  * Release ImageMagick version 7.0.7-12, GIT revision 21814:5ef2c5a67:20171129.

2017-11-12  7.0.7-12 Cristy  <quetzlzacatenango@image...>
  * The -tint option no longer munges the alpha channel (reference
    http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=33070).
  * Don't delete in-memory blob when reading an image (reference
    https://github.com/ImageMagick/ImageMagick/issues/886).
  * Support HDRI color profile management.