`RemoteDocPresence` mutates the prototype of `RemotePresence`

[alecgibson]

This was probably a typo 🙈

sharedb/lib/client/presence/remote-doc-presence.js

Lines 79 to 89 in 3552c28

	RemotePresence.prototype._handleCreateDel = function() {
	this._cacheOp(null);
	this._setPendingPresence();
	};
	RemotePresence.prototype._handleLoad = function() {
	this.value = null;
	this._pending = null;
	this._opCache = null;
	this.presence._updateRemotePresence(this);
	};