BUG In Travis, restrict pandas version downloaded

.travis.yml

@@ -7,7 +7,6 @@ python:
 install:
     - pip install --upgrade pip setuptools
     - pip install -r dev-requirements.txt
-    - pip install pandas scikit-learn scipy feather-format
     - pip install -e .
 env:
   global:

CHANGELOG.md

@@ -10,6 +10,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 - Include JSON files with pip distributions (#244)
 - Added flush to `civis_to_file` when passed a user-created buffer,
   ensuring the buffer contains the entire file when subsequently read.
+- Travis tests for Python 3.4 are now restricted to pandas<=0.20, the
+  last version which supported Python 3.4 (#249)
 
 ### Added
 - Added a utility function which can robustly split a Redshift schema name

dev-requirements.txt

@@ -6,4 +6,11 @@ pytest-cov>=2.4.0,==2.*
 vcrpy>=1.11.0,<=1.11.99
 vcrpy-unittest==0.1.6
 sphinx_rtd_theme>=0.2.4,<1.0.0
-numpydoc>=0.7.0,<1.0.0
+numpydoc>=0.7.0,<1.0.0
+feather-format
+numpy
+pandas; python_version >= '3.5'
+pandas<0.21; python_version == '3.4'
+pandas<=0.23; python_version == '2.7'
+scikit-learn
+scipy