[appveyor] Don't nupkg for pull requests.
Merge pull request #279 from chrisdembia/appveyor-nuget-l

[appveyor] Don't nupkg for pull requests.
Merge pull request #281 from simbody/contributing-md

[WIP] Fill in CONTRIBUTING.md instructions
[travis] Fail if tabs found in CMake, cpp, c, h.
Merge pull request #282 from simbody/getRidOfAllTabs

Get rid of all tabs
[travis] Apply @sherm1's stringent no-tabs policy.

More filetypes now need to obey no-tabs policy: .md .yml .cmake .xml .html .in
[travis] Test for tabs before all else.
[travis] no-tab check had redundant CMakeLists.txt
[travis] only perform no-tab check on linux.
Merge pull request #283 from chrisdembia/travis-fail

[travis] Fail if tabs found in CMake, cpp, c, h.
Add a ".txt" suffix to the LICENSE file so that scripts will have an easier time dealing with it.
Merge branch 'master' of https://github.com/simbody/simbody
Merge pull request #284 from simbody/master

Get rid of all remaining tabs in the Simbody repo