COMPAT: Make is_number import backwards-compat (#309)

Author: gfyoung

.travis.yml

@@ -48,4 +48,3 @@ script:
 
 after_success:
   - coveralls
-

pandas_datareader/compat/__init__.py

@@ -1,2 +1,11 @@
 # flake8: noqa
+import pandas as pd
+
 from io import BytesIO
+from distutils.version import LooseVersion
+
+pandas_version = LooseVersion(pd.__version__)
+if pandas_version <= '0.19.2':
+    from pandas.core.common import is_number
+else:
+    from pandas.api.types import is_number

pandas_datareader/edgar.py

@@ -3,16 +3,13 @@
 from ftplib import FTP
 import gzip
 
-from pandas import read_csv
-from pandas import DataFrame
-from pandas import to_datetime
 from zipfile import ZipFile
 from pandas.compat import StringIO
-from pandas.api.types import is_number
+from pandas import read_csv, DataFrame, to_datetime
 
 from pandas_datareader.base import _BaseReader
-from pandas_datareader.compat import BytesIO
 from pandas_datareader._utils import RemoteDataError
+from pandas_datareader.compat import BytesIO, is_number
 
 
 _URL_FULL = 'edgar/full-index/master.zip'