Remove interface for adding new LiveChat widgets

[jwfuller]

Now that JS Includes are merged, we can start closing down LiveChat

[AlanBCole]

Questions:

• Is simply deleting the cu_livechat_bundle not satisfactory?:
• Are there steps that have been decided on already?
• Is there a need to notify users who may be using livechat previously to the cu_js_include module?

[jwfuller]

• Is simply deleting the cu_livechat_bundle not satisfactory?
  • No, people are using the bundle and deleting it would break their sites
• Are there steps that have been decided on already?
  • Generally, we deprecate a feature, migrate people to the new alternative, disable the code, delete the code.
• Is there a need to notify users who may be using livechat previously to the cu_js_include module?
  • Yes, we need to do this as part of this. Atlas Statistics or it's successor can help us with this