DEPS: Drop Python 3.4 support (pandas-dev#16303)

* DEPS: Drop Python 3.4 support

Closes pandas-devgh-15251.

* TST: Patch locale failure on Circle

Author: gfyoung

ci/requirements-3.4.build

@@ -1,6 +1,6 @@
-python=3.4*
+python=3.6*
 python-dateutil
 pytz
 nomkl
-numpy=1.10*
+numpy
 cython

ci/requirements-3.4.pip

@@ -0,0 +1,22 @@
+python-dateutil
+pytz
+numpy
+scipy
+openpyxl
+xlsxwriter
+xlrd
+xlwt
+numexpr
+pytables
+matplotlib
+lxml
+html5lib
+jinja2
+sqlalchemy
+pymysql
+# feather-format (not available on defaults ATM)
+# psycopg2 (not avail on defaults ATM)
+beautifulsoup4
+s3fs
+xarray
+ipython

ci/requirements-3.4.run

@@ -0,0 +1,6 @@
+python=3.6*
+python-dateutil
+pytz
+nomkl
+numpy
+cython