Missing engine Config

[jbourassa]

Not all configuration options are available. Go through the list of Wasmtime's Config and implement the ones that are relevant.

[jbourassa]

I'm thinking of changing the config to take in a Hash of options instead of a Config instance, removing the Config class altogether. This is quite natural in Ruby and lends itself to this API: the config is basically all scalars, and new engines aren't created very often, so the cost of hashing is negligible.

Current API:

config = Config.new
config.epoch_interruption = true
config.consume_fuel = true
engine = Engine.new(config)

Proposed API:

engine = Engine.new(epoch_interruption: true, consume_fuel: true)

Alternatively, if we think we have to keep the Config class, I'd wanna change it to a builder-style API -- I think it's quite elegant for this use case.

config = Config.new
  .epoch_interruption(true)
  .consume_fuel(true)
engine = Engine.new(config)