rules must reference this.rules in renderInline

today i wrote my first 'remarkable' extension (which can be studied here: https://gist.github.com/loveencounterflow/9d893beb37d12ad456fd). it looks like https://github.com/jonschlinkert/remarkable/blob/dev/lib/renderer.js#L293 should be patched so changes to the rules effected by `parser.use()` are properly reflected. 

may i also suggest to link my gist in your README.md until better documentation is available? the relevant issues are sort of hard to find and hard to piece together.