Bugfix: inconsistent kwarg documentation + test case for the windowing operator

There was a disagreement between the option name (skip_empty and
skip_missing) that broke the test cases and would have been confusing.
Bugfix: if the paste sort key was 'uuid' it would clober that tag and break
subsequent operators
Add test travis file
Tweak travis script
Remove deprecated BeautifulSoup dependency
Enable site packages, system numpy+scipy for faster CI builds
Tweak deps for CI.
Update README.md
Another tweak to try to get site packages working
Another tweak to try to get site packages working: only build on 2.7 since that is where numpy/scipy are supported
Merge branch 'master' of github.com:SoftwareDefinedBuildings/smap
Merge remote-tracking branch 'origin/master' into openbas
Install instructions point to github instead of svn
Merge master
Remove old VM link, point to releases
Forgot a period
Merge remote-tracking branch 'origin/master' into events
Fix content-type of JSON consumers.  This have broken clients expecting
(reasonably) the content-type header to be set correctly.
Merge branch 'master' of github.com:SoftwareDefinedBuildings/smap
remove trailing whitespace