New Features:
- Bump the required version of GLib to 2.68 (Richard Hughes)
Bugfixes:
- Do not construct an invalid silo when processing more than 30 attrs (Richard Hughes)
- Fix NULL pointer dereference when searching with NULL needle (Richard Hughes)
- Fix potential use-after-free when building the in() haystack (Richard Hughes)
- Fix stem() type-checking the wrong stack position (Richard Hughes)
- Handle NULL string opcodes in more functions (Richard Hughes)
- Limit operator recursion depth in xb_machine_parse_section (Richard Hughes)
- Limit the number of predicates and OR branches in each section (Richard Hughes)
- Prevent an infinite loop when parsing a corrupt silo (Richard Hughes)
- Reject XML with more than 65535 unique element names (Richard Hughes)