New Puppet Abstract API: `onStart()` & `onStop`

[huan]

Wechaty Puppet v0.49 and the previous version, we need to implement the start() and stop() on child class, and we need to manage the state by ourselves, like:

puppet/src/puppet/puppet.ts

Lines 138 to 142 in e76d675

	if (this.state.on()) {
	log.warn('Puppet', 'start() found that is starting/statred...')
	await this.state.ready('on')
	log.warn('Puppet', 'start() found that is starting/statred... done')
	return

From v0.51, we can reuse those codes from the abstract base class, and we can put all our function code in onStart() and onStop(), without care about the state anymore.

The start() and stop() method in the Puppet abstract base class will take care of the state and call onStart() and onStop for you.

• Wechaty Puppet API v1.0 Adaptions #164