readme.md missing some endpoints

[zatziky]

'API - methods' missing:

• channels
• settings

'API - methods' change:

• remove HTTP and Endpoint columns
• merge Method and Argument as Method (e.g. amioApi.contacts.get(channelId, contactId))

'Webhooks setup & usage' missing:

• opt-in (check if it's in code)

Jenom drobna chyba ve vete - mezera na konci pred carkou :-)

• It responds OK 200 to Amio .