phase2: use full git history for reproducibility

phase2: use full git history for reproducibility

The SOURCE_DATE_EPOCH variable is used to set reproducible time stamps
for built artifact. As packages get rebuild without changing, they
require individual epochs which are independent of the main tree. To
archive that the git log for each package source path is used.

This mechanism can only work if the full git history is available. Until
now only a shallow copy (--depth 1) would be cloned. With this commit
the `feeds.conf.default` is changed to use the full git repository.

Signed-off-by: Paul Spooren <mail@aparcar.org>
[do not modify feeds.conf.default]
Signed-off-by: Jo-Philipp Wich <jo@mein.io>