implement user preference for elevation plots starting at zero;

add docker make command to downgrade db;
add (google-powered) translations for the new labels

fittrackee/migrations/versions/31_db58d195c5bf_add_start_elevation_at_zero.py

@@ -0,0 +1,35 @@
+"""add user preference to start elevation plots at zero
+
+Revision ID: db58d195c5bf
+Revises: 374a670efe23
+Create Date: 2023-03-14 04:14:23.781672
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'db58d195c5bf'
+down_revision = '374a670efe23'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('users', schema=None) as batch_op:
+        batch_op.add_column(sa.Column('start_elevation_at_zero', sa.Boolean(), nullable=True))
+    op.execute("UPDATE users SET start_elevation_at_zero = true")
+    op.alter_column('users', 'start_elevation_at_zero', nullable=False)
+
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('users', schema=None) as batch_op:
+        batch_op.drop_column('start_elevation_at_zero')
+
+    # ### end Alembic commands ###