[writer] Shorthandable tags are not shorthanded #258

Hello

I'm using this library to parse a configuration format where I added some custom types. These custom types are constructed and represented through some types I'm writing. All of the types are collected in a custom schema. (By the way, schemas work great and makes the library very extensible :)

Below I copy the input I'm parsing:

d: !!lp/fnref log

And this is the output I get after loading the YAML text and dumping the data structure

d: !<tag:yaml.org,2002:lp/fnref> log

Is there anyway I can tell js-yaml to dump tag names in the short representation I used in the input?