refactor(BitField): base class for Permissions, ActivityFlags, Speaking (#2765)

* abstract BitField from Permissions

* reduce useless code, improve docs

* add a ReadOnly identifier to the return type of Bitfield#freeze()

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-1.html#partial-readonly-record-and-pick

* fix the RangeError

* update docs, convert Speaking and ActivityFlags to bitfields

* fix some docs

* Fix Speaking BitField oops

* docs for oops

* more incorrect docs

* Fix incorrectly named property

* add new classes to index

* fix missing @extends docs

* default bitfield resolve to 0, and cleanup defaulting everywhere

Also removes GuildMember#missiongPermissions() alias that had incorrect behavior

* Breaking: Rename Overwrite allowed and denied to allow and deny

To be consistent with the api's naming

* fix setSpeaking usage to bitfields instead of booleans

* fix speaking bug in playChunk

* docs: Updated typings

* fix: BitFieldResolvable should use RecursiveArray

* bugfix/requested change

* typings: Cleanup (#2)

* typings: Fix BitField#{toArray,@@iterator} output type

* typings: correct PermissionOverwrites property names and nitpicks

src/stores/GuildChannelStore.js

@@ -24,8 +24,8 @@ class GuildChannelStore extends DataStore {
   /**
    * Can be used to overwrite permissions when creating a channel.
    * @typedef {Object} PermissionOverwriteOptions
-   * @property {PermissionResolvable} [allowed] The permissions to allow
-   * @property {PermissionResolvable} [denied] The permissions to deny
+   * @property {PermissionResolvable} [allow] The permissions to allow
+   * @property {PermissionResolvable} [deny] The permissions to deny
    * @property {RoleResolvable|UserResolvable} id ID of the role or member this overwrite is for
    */
 
@@ -54,7 +54,7 @@ class GuildChannelStore extends DataStore {
    *   overwrites: [
    *      {
    *        id: message.author.id,
-   *        denied: ['VIEW_CHANNEL'],
+   *        deny: ['VIEW_CHANNEL'],
    *     },
    *   ],
    * })