New stuff:
----------
 * Add FEATURE_ environment variables for MKL, opt and debugging #978
 * add info/about.json file that contains the "about" section of meta.yaml #941
 * allow ```--dirty``` flag to be passed to ```conda build``` command. Skips
   download, and provides DIRTY environment variable in build scripts. #973
 * Add msys2 paths to build and test environments #979
 * add new x86 and x86_64 selectors for Intel platforms #986
 * keep original meta.yaml in recipe folder of package; create meta.yaml.rendered in recipe folder.  Neither exist when recipe not included.  #1004
 * add ignore_prefix_files key to build in meta.yaml. Can ignore list of files,
   or True to ignore all prefix files. #1008 #1009
 * Automatically determine patch strip level #1011

Bug fixes/Improvements:
-----------------------
 * Lightened requirement that x.x be defined in both build and runtime sections.  #650
 * Remove info/recipe.json from build conda packages.  Superseded by info/recipe/meta.yaml.rendered.  #781
 * Search for single and double backslashes when finding files that need prefix replacement #962
 * Track undefined jinja variables and use them to decide whether to download source #964
 * handle patches with p0 or p1 #969, #1011, #1020
 * only set os.environ for non-None variables #981
 * Don't use long prefixes on windows #985
 * Fix missing encoding argument #987
 * Respect proxy variables more appropriately #989
 * Search packages on PyPI, rather than listing them all.  Should avoid some timeout errors there. #991
 * Fix unix-style paths returned from git on Windows preventing relative paths from providing Jinja2 metadata #995
 * improve logic handling "dirty" downloading.  Always download when not dirty.  #995
 * Fix post-build variables when no build section existed in original meta.yaml #999
 * Activate _build and _test environments approriately, rather than manipulating PATH directly #1002
 * Don't clone git submodules until after first checkout #1025
 * Move check_install over from conda.install #1027

Deprecations:
-------------
 * __conda_version__.txt and other post-build methods of altering the build
   string are marked as deprecated. Prefer Jinja2 templates where possible.
   Create issues if this breaks your work.

Contributors:
-------------
 * @filmor
 * @ilanschnell
 * @jschueller
 * @mingwandroid
 * @msarahan
 * @pelson
 * @stuarteberg
 * @whitequark