support for pathlib object when saving Element (#103)

* support for pathlib object

* Path is the parent for Windows Path and non-Windows Path objects

Co-authored-by: Will Dean <wdean@homepartners.com>
Co-authored-by: Will <swilliam127@gmail.com>

branca/element.py

@@ -14,6 +14,7 @@
 from urllib.request import urlopen
 from binascii import hexlify
 from os import urandom
+from pathlib import Path
 
 from jinja2 import Environment, PackageLoader, Template
 
@@ -159,7 +160,7 @@ def save(self, outfile, close_file=True, **kwargs):
         close_file : bool, default True
             Whether the file has to be closed after write.
         """
-        if isinstance(outfile, str) or isinstance(outfile, bytes):
+        if isinstance(outfile, (str, bytes, Path)):
             fid = open(outfile, 'wb')
         else:
             fid = outfile