Improve the health of this package (#1428)

.travis.yml

@@ -1,7 +1,6 @@
 language: python
 
 python:
-- '2.6'  # TODO remove in v0.11.0
 - '2.7'
 - '3.3'
 - '3.4'
@@ -43,7 +42,11 @@ before_script:
 script:
 - tox -e $(echo py$TRAVIS_PYTHON_VERSION-mg$PYMONGO | tr -d . | sed -e 's/pypypy/pypy/') -- --with-coverage
 
-after_script: coveralls --verbose
+# For now only submit coveralls for Python v2.7. Python v3.x currently shows
+# 0% coverage. That's caused by 'use_2to3', which builds the py3-compatible
+# code in a separate dir and runs tests on that.
+after_script:
+- if [[ $TRAVIS_PYTHON_VERSION == '2.7' ]]; then coveralls --verbose; fi
 
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