Initial work on #74. (#514)

* Initial work on #74.

* Fixing tests.

* Adding migration script.

* Excluding migrations from coverage report.

lemur/migrations/versions/6d6151f5f307_.py

@@ -0,0 +1,36 @@
+"""Adding private key auditing.
+
+Revision ID: 6d6151f5f307
+Revises: 932525b82f1a
+Create Date: 2016-11-18 16:08:12.191959
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '6d6151f5f307'
+down_revision = '932525b82f1a'
+
+from alembic import op
+import sqlalchemy as sa
+
+from sqlalchemy_utils.types import ArrowType
+
+
+def upgrade():
+    ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('views',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('certificate_id', sa.Integer(), nullable=True),
+    sa.Column('viewed_at', ArrowType(), server_default=sa.text('now()'), nullable=False),
+    sa.Column('user_id', sa.Integer(), nullable=True),
+    sa.ForeignKeyConstraint(['certificate_id'], ['certificates.id'], ),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    ### end Alembic commands ###
+
+
+def downgrade():
+    ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('views')
+    ### end Alembic commands ###