Merge pull request #226 from shoyer/add-travis

Add .travis.yml for Travis-CI
have travis run test/run_all.py, send email
update to trigger travis
make shell script for travis to run
update
remove test script
update
update
turn off email notifications
Merge pull request #227 from jswhit/master

fix .travis.yml so it runs test/run_all.py
silence warnings, remove cruft from run_all.py, explain what tests are
skipped.
Merge pull request #228 from jswhit/master

silence warnings, remove cruft from run_all.py, print skipped tests
add item for issue 225
Merge pull request #229 from jswhit/master

add item for issue 225
fix python 3 print
fix python 3 print
Merge pull request #230 from jswhit/master

fix python 3 print
change error message when Dataset has been garbage collected.
Merge pull request #231 from jswhit/master

change error message when Dataset has been garbage collected.
Allow creating and setting variables with numpy string arrays

This patch automatically converts numpy string datatypes of length > 1 into
`str` when used as arguments to `createVariable`, and allows for setting
arrays with numpy string datatypes (they are converted internally into arrays
with dtype=object, but the user doesn't need to know that detail).

The reason for this patch is for consistency: I expected that if `array.dtype`
is not a valid argument argument to `createVariable`, then it isn't possible
to create (or fill) a Variable with the values of the `numpy.ndarray` `array`.
Strings are the exception to this rule. This patch eliminates this quirk in a
manner that I believe will be backwards compatible, since only strings of
length 1 (character arrays) are a supported primitive datatype.

If this looks good to you, I will add this feature to the Change Log and the
documentation in my next commit.