Remove get_license() from Submission class

* Not supported by JSON schema or HEPData web application.

hepdata_lib/__init__.py

@@ -562,17 +562,6 @@ def __init__(self):
             "Created with hepdata_lib " + __version__,
             "https://doi.org/10.5281/zenodo.1217998")
 
-    @staticmethod
-    def get_license():
-        """Return the default license."""
-        data_license = {}
-        data_license["name"] = "cc-by-4.0"
-        data_license["url"] = "https://creativecommons.org/licenses/by/4.0/"
-        data_license[
-            "description"] = "The content can be shared and adapted but you must\
-             give appropriate credit and cannot restrict access to others."
-        return data_license
-
     def add_table(self, table):
         """Append table to tables list.
 
@@ -667,7 +656,6 @@ def create_files(self, outdir=".", validate=True, remove_old=False):
 
         # Write general info about submission
         submission = {}
-        submission["data_license"] = self.get_license()
         submission["comment"] = self.comment
         submission["related_to_hepdata_records"] = self.related_records