Testing an initial Travis-CI setup

[jhuntwork]

@pierre-labastie - this should have triggered a run with Travis-CI if the repo is configured with Checks. Can you take a look?

[pierre-labastie]

Since I am new to this, I think I cannot tell whether it is good or not, although I trust you, of course. I have a couple questions, mainly for learning:

• will this trigger checks on all branches or only master?
• (related to first question) what is the directory layout for travis? Is wd the top directory of the project, or is it wd/jhalfs? In the first case, the check is adapted to the pythonize branch, while in the second case, it is adapted to master... It seems to me that it cannot be adapted to both, unless there is some hidden magic.