Merge pull request #421 from nkeim/remove-travis-badge

DOC: Remove defunct Travis CI badge from README

Author: nkeim

README.md

@@ -1,8 +1,6 @@
 pims: Python Image Sequence
 =========================
 
-[![build status](https://travis-ci.org/soft-matter/pims.png?branch=master)](https://travis-ci.org/soft-matter/pims)
-
 What Problem Does PIMS Solve?
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