Describe available fields for engine

[qfox]

Atm readme doesn't provide any information about engines options except some basics.
There are caveats that should be described: https://github.com/enb-bem/enb-bem-tmpl-specs/blob/master/lib/plugin.js#L62-67

[blond]

fixed now?

[qfox]

Ops. Not fully. Probably it'd be good to note exportName of options since it's used in lib/plugin.js: https://github.com/enb-bem/enb-bem-tmpl-specs/blob/master/lib/plugin.js#L52

[qfox]

For sure the best way here to move these hacks out of code base. In this case we can just note that in code and close the issue.

Off-topic: Also I thought about moving async into tech itself (or to use apply.length to detect it automatically), but it could break something in future.

[blond]

exportName is option of bemhtml tech. Description this option is in the engine packages: enb-bemxjst and enb-xjst. Why to describe it in documentation of this package?

[qfox]

@andrewblond Because it's used in code. That's why I want to note these lines in code as hardcoded, make an issue to move these func-ty out, and close this issue. ;-)

[blond]

@zxqfox I don't want to describe exportName in the documentation. If you have an opinion how to get rid of hard code — do it! ;)

[qfox]

@andrewblond Okay. Issue for hardcoded exportName: #67

Let's close this!