Proposal: dependency wechaty-puppet-service from wechaty

[huan]

After working on Python Wechaty (polyglot as well) for a year, I believe the wechaty-puppet-service will be the default Python Wechaty puppet and the only one implementation for a long time.

So why not dependency it from Wechaty directly (like TS), so that we can make our requirements.txt to be clearer?

python-wechaty-getting-started/requirements.txt

Lines 1 to 2 in b94d12e

	wechaty~=0.6
	wechaty-puppet-service~=0.5.0dev

After this change, the above two lines will become one line: wechaty~=0.6