Reduce bundlesize by picking parts of fontawesome and d3
Add mixings for subscribing components

To allow hot reloading for templates and resources add according
properties.
Add instructions in the README.md on how to develop the ui

Don't output metadata in Registration.toString()

Don't output metadata in Registration.toString()

The Spring team discourages the use of the `spring.*` configuration
namespace, hence I use the major update and move all properties. With
this commit all client related properties are moved to `sbadmin.client`.

Added documentation and a sample on how to secure the SBA-Server and
leverage the new login ui-module

closes #361

With this change it is possible to include credentials in the instance
metadata which will then be used to access the client endpoints using
HTTP Basic authorization.

closes #359

As now with spring boot 1.4 there is a special goal for generating the build-
information, we use it for displaying the version in spring boot admin. The old
info.version property still works but is deprecated. From now on
build.info.version is taken into account.

With this commit urls form the /info endpoint are deteceted and rendered as
links.
The downside is to make that work I had to drop the collapsible info section in
the overview list and replaced it with an resizable/scrollabe <pre> section.

The polling in the UI is replaced with server side events. Status changes are
now reported immediately from the admin server to the UI.

fixes #61

To enable, you just have to add a DiscoveryClient to your Spring Boot Admin Server.
Also did some code polish.
Closes #44