Revert "chore, revert max-quote-age feature again"

This reverts commit e62e3e3410f11562f16f829ae6f610ffad9dd492.
hygiene, turn instant inlines pure+const

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, provide inlines to compare idiffs

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, allow negative duration addition and fix up results accordingly

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, technically allow max-quote-age

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, reset fortify level to 0 in coru.h to turn off longjmp stack check

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'core/coru-slju'

* core/coru-slju:
  chore, reset fortify level to 0 in coru.h to turn off longjmp stack check
minor, provide a reader for echs_idiff_t objects

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, introduce --max-quote-age (for filter and glue)

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'feat/max-quote-age'

* feat/max-quote-age:
  minor, introduce --max-quote-age (for filter and glue)
  minor, provide a reader for echs_idiff_t objects
  minor, technically allow max-quote-age
  minor, allow negative duration addition and fix up results accordingly
  minor, provide inlines to compare idiffs
  hygiene, turn instant inlines pure+const
  Revert "chore, revert max-quote-age feature again"