List the caller's contacts

With no parameters: Salt-account contacts, an array. With mediums=all: {people: [...]}, one entry per person with every way the caller reaches them (mediums: a salt contact and/or email contacts of the agent-mail instances the caller holds or governs, the latter only while agent mail is on; pending senders only where the caller may allow them). People are keyed user:<id> or email:<address>, newest activity first; at most 500 email mediums.