loader: Rename start_from_scratch parameter to incremental
This:
- unifies this parameter with the equivalent one in the git loader.
- also documents it
Related to #3695 Depends on !58 (closed)
Test Plan
tox
Migrated from D6576 (view on Phabricator)
This:
Related to #3695 Depends on !58 (closed)
tox
Migrated from D6576 (view on Phabricator)