Enhancements:
-------------

* pass WINDIR env var through on Windows  #1837
* make long test prefix an option (default disabled)  #1838

Bug fixes:
----------

* monkeypatch ensure_use_local to avoid conda-build import clobbering conda CLI arguments  #1834
* Fix context conda_build attr error with older conda  #1813
* Fix legacy noarch shebang replacement code to account for long prefix paths #1813
* properly initialize 'system' key in linkage inspecting #1839
* backport try mmap from master #1764
* fix wheel output not respecting --output-folder CLI argument #1838
* catch csv dialect sniffing error, try to fallback to to excel_tab.  Might work? #1840