Log Message:
graphite2: Update to 1.3.13

1.3.13
- Resolve minor spacing issue in rtl non-overlap kerning
- python3 for graphite.py
- Better fuzzing
- Better building on windows

1.3.12
- Graphite no longer does dumb rendering for fonts with no smarts
- Segment caching code removed. Anything attempting to use the segment cache \ 
gets given a regular face instead
- Add libfuzzer support
- Builds now require C++11
- Improvements to Windows 64 bit builds
- Support different versions of python including 32 bit and python 3
- Various minor bug fixes