Update SocketIORouter.js

Changed the setting of client.remoteAddress
updated to use settings

updated handler/SocketIORouter.js to use new setting
updated hooks/express.js to use new setting
updated utils/Settings.js to accept new setting
updated settings.json.template so new setting is present
Simpify CSS for sticky chat
pass pad in postAceInit hook

no way for plugins to access current pad otherwise.
Add userLeave hook
export sessioninfos so plugins can access it

allows plugins to map client.id to author id
Merge pull request #1815 from bit/patches

Some Patches
repo url as latest npm shows warn if non existant
Update LICENSE
Update README.md
Make pads with long lines usable with chrome.

- Do not use incorpIfQuick on keyup because it's not ever quick
  on chrome. Calling incorpIfQuick calls incorporateUserChanges
  which sets a flag on the current callstack state indicating
  that the selection has changed (since something was typed).
  Whenever this flag is set, the event handler will run code
  to update the selection (and possibly scroll the view as
  well), which is a very costly operation in webkit browsers.
  Instead let the user changes be incorporated by the idle worker,
  scheduling it to run ASAP on keyup. This isn't a perfect
  solution, but may make pads running on webkit browsers more
  usable with otherwise fairly unnoticeable changes in the UI.
Adapt and add slowness test from @JohnMcLear.

- The test now ensures that all three key events are fired when
  sending keys. Previously, only the 'keypress' event was sent,
  which failed to trigger very slow code on webkit browsers (as
  it is triggered by 'keyup'). All three events should really be
  sent whenever sending keys to the browser to ensure that we're
  adequately testing real behavior. See the 'sendkeys' plugin
  for more; it only sends 'keypress'.
Localisation updates from http://translatewiki.net.
Merge pull request #1833 from digitalbazaar/fix-chrome-longlines-slowdown

Make pads with long lines usable with chrome.
Grammar fix
Merge pull request #1837 from rgbkrk/patch-1

Grammar fix
Update en.sjon translation

pad.importExport.abiword.innerHTML
Localisation updates from http://translatewiki.net.
Update html10n.js
Make use of the new plural macro