Add column for task links

Adds column in task table for link to a resource, and a migration.
Once the api and UI are updated, this will let a user include a link to
a resource in a task.

Change-Id: I2ad96cc6b6728815e7b6a04a92e4b99c3aebff98

storyboard/db/migration/alembic_migrations/versions/052_add_column_for_task_links.py

@@ -0,0 +1,38 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+
+"""task-links
+
+Revision ID: 052
+Revises: 051
+Create Date: 2016-02-08 15:58:59.451550
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '052'
+down_revision = '051'
+
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade(active_plugins=None, options=None):
+
+    op.add_column('tasks', sa.Column('link', sa.UnicodeText(), nullable=True))
+
+
+def downgrade(active_plugins=None, options=None):
+
+    op.drop_column('tasks', 'link')

storyboard/db/models.py

@@ -331,6 +331,7 @@ class Task(FullText, ModelBuilder, Base):
 
     creator_id = Column(Integer, ForeignKey('users.id'))
     title = Column(Unicode(CommonLength.top_large_length), nullable=True)
+    link = Column(UnicodeText())
     status = Column(Enum(*TASK_STATUSES.keys()), default='todo')
     story_id = Column(Integer, ForeignKey('stories.id'))
     project_id = Column(Integer, ForeignKey('projects.id'))