Add default points to assignments

- Add field to assignments
- Take default points in account when calculating assignment grades
Update SQL: add default_points field

- to gradebook_assignments table
Gradebook grades fixes

- Div true for saved grades
- bugfix: display letter & percent grade in "All"
Bugfix: input data verification
Bugfix: input data verification
Total in red in using default points not saved
Revert "Total in red in using default points not saved"

This reverts commit 1ae8bd3c92bc0430aaed12ee3c7433538c3c32b4.
Revert "Revert "Total in red in using default points not saved""

This reverts commit 8015c8b00adf5c61b0dbd0909cf596a4bacd25ae.
assignments appear after assigned date & not due date
Remove PARTIAL_USE_DEFAULT_POINTS
Revert "assignments appear after assigned date & not due date"

This reverts commit c9bdcbc437abafe9ea6ebbd6781a791fe6ace24f.
Bugfix check numeric fields
Bugfix broken statistics

MIN calculus fix when gg.POINTS is NULL
Bugfix check numeric fields
Add date field support
Bugfix SQL error staff_field_seq
Bugfix check numeric fields
Bugfix check numeric fields
Bugfix check numeric fields
Fix people fields display