Added requirements for requires.io [skip ci]

Author: Chilipp

requirements.txt

@@ -0,0 +1,16 @@
+# Matplotlib
+#   https://github.com/matplotlib/matplotlib/blob/master/CHANGELOG
+matplotlib==2.0.2  # rq.filter: >=1.4, <2.1
+
+# xarray
+#   https://github.com/pydata/xarray/blob/stable/doc/whats-new.rst
+xarray==0.9.6  # rq.filter: >=0.7.0, < 1.0
+
+# pandas
+#   http://pandas.pydata.org/pandas-docs/stable/whatsnew.html
+pandas==0.20.3 # rq.filter: >= 0.18.0, < 0.21
+
+# cartopy
+#   http://scitools.org.uk/cartopy/docs/latest/whats_new.html
+cartopy==0.15.1 # rq.filter: >= 0.13, < 0.16
+