Improved client_hash_check

- Added option to disable hash check by GM group_id (specify 'disabled'
  as hash for a certain group_id to let them log in with any client,
  even if client_hash_check is enabled
- Updated and reworded related documentation for the feature, following
  user feedback about certain parts being incomplete or confusing.
Added get_substring to the libpcre interface

Signed-off-by: Haru <haru@dotalux.com>
Fixed vending title escaping

Thanks to Haruna

Signed-off-by: shennetsind <ind@henn.et>
Fixed Bug 7978

Consumables with expire item no longer stack with those without expire time
Thanks to kyeme.
http://hercules.ws/board/tracker/issue-7978-rental-item-stackable/

Signed-off-by: shennetsind <ind@henn.et>
Improved script case check reports to include more accurate source info.

- Fixes bugreport:8013, thanks to Dastgir Pojee
  http://hercules.ws/board/tracker/issue-8013-script-add-str-problem/

Signed-off-by: Haru <haru@dotalux.com>
Follow-up to 7b19f964b88dffcfdc8c12648d5e4ee8a26a9504

- Fixes bugreport:8015, thanks to N e s s
  http://hercules.ws/board/tracker/issue-8015-error-in-compiling-in-debian-linux-latest-rev/

Signed-off-by: Haru <haru@dotalux.com>
Fixed Bug#7929
-http://hercules.ws/board/tracker/issue-7929-overbrand-and-mapflags/?gopid=21542#entry21542
Fixed Bug#7966
-http://hercules.ws/board/tracker/issue-7966-over-brand/

Signed-off-by: malufett <malufett.eat.my.binaries@gmail.com>
Report 7964.
Removed leftover constants. Thanks to AnnieRuru for bringing it up.