Fix @context on actor, note, activity, and collection objects

[johnspurlock]

Need to include the non-activitystreams terms in your context array

e.g. https://browser.pub/https://ap.podcastindex.org/podcasts?id=920666

currently:

"@context": [
    "https://www.w3.org/ns/activitystreams",
    "https://w3id.org/security/v1"
],

should be:

"@context": [
    "https://www.w3.org/ns/activitystreams",
    "https://w3id.org/security/v1",
    {
        "toot": "http://joinmastodon.org/ns#",
        "discoverable": "toot:discoverable",
        "indexable": "toot:indexable",
        "memorial": "toot:memorial",
        "featured": {
            "@id": "toot:featured",
            "@type": "@id"
        }
    }
]

Similiarly in Note objects

e.g. https://browser.pub/https://ap.podcastindex.org/episodes?id=920666&statusid=0

(and activities e.g. https://ap.podcastindex.org/episodes?id=920666&statusid=PC20-190&resource=activity)

currently:

"@context": [
    "https://www.w3.org/ns/activitystreams"
],

should be:

"@context": [
    "https://www.w3.org/ns/activitystreams",
    "https://w3id.org/security/v1",
    {
        "ostatus": "http://ostatus.org#",
        "conversation": "ostatus:conversation"
    }
]

And in outbox collections:

e.g. https://browser.pub/https://ap.podcastindex.org/outbox?id=920666&page=true

currently:

"@context": "https://www.w3.org/ns/activitystreams",

should be:

"@context": [
    "https://www.w3.org/ns/activitystreams",
    {
        "ostatus": "http://ostatus.org#",
        "conversation": "ostatus:conversation",
        "litepub": "http://litepub.social/ns#",
        "directMessage": "litepub:directMessage"
    }
]