adds backend script which can be run as a cronjob every n minutes to generate new json files for google calendars

- database updated to save google credentials
- database updated to save json calendar information
- json still saved as a json file under userinfo/<user.id>/calendarevents.json

migrations/versions/66f62f457a22_.py

@@ -0,0 +1,28 @@
+"""empty message
+
+Revision ID: 66f62f457a22
+Revises: 7bbc2215d87d
+Create Date: 2020-04-24 17:12:45.275636
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '66f62f457a22'
+down_revision = '7bbc2215d87d'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('user', sa.Column('google_credentials', sa.String(), nullable=True))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('user', 'google_credentials')
+    # ### end Alembic commands ###

migrations/versions/7bbc2215d87d_.py

@@ -0,0 +1,28 @@
+"""empty message
+
+Revision ID: 7bbc2215d87d
+Revises: 92db2e496087
+Create Date: 2020-04-24 11:36:43.600038
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '7bbc2215d87d'
+down_revision = '92db2e496087'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('user', sa.Column('calendarJson', sa.String(), nullable=True))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('user', 'calendarJson')
+    # ### end Alembic commands ###