Make REST_API a global define and make it a C string
Let NSURL extract the host from REST_API

The custom code in network::can_reach_host only dealt with the scheme, not port number or user/password.
Hide link arrows in Preferences → Bundles when there is no link
Use file’s display name instead of CFBundleName

This seems to be what Finder does, and some bundles (Spotify.app) actually lack a CFBundleName key.

Also ensure our bundle has a CFBundleIdentifier.
Do not update a bundle if it requires a newer version of TextMate
Fix error logging for download problems
Make bundle update frequency configurable

This is introduced only for testing.
Show an error when WebKit fails to load the requested resource

WebKit will e.g. fail to load resources identified as application/octet-stream.
Remove backup files for documents with a path during quit

Previously if we selected “Don’t Save” the discarded changes would still be there after relaunch.