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

To easily add new mvc controllers (e.g. from extensions) a new
annotation `@AdminController` is added.

As it turns out (rather obvious) that the ThreadPools for registration and
status updating needs to be destroyed on application shutdown so that the
worker threads gets cancelled. To achieve this we simply register the
ThreadPools as spring beans (since they are implementing DisposableBean).

fixes #253

Fix the usage of RestTemplateBuilders which wasn't covered by PR #247

closes #201

With this commit the icons from FontAwesome are used. To achive this the
webpack css-loader is used and the location for the module.css has slightly
changed.
Also I removed the ugly sidebar (what a short life) and added a slim navbar at
the top for the detail views.

 - Updated Angular to 1.5.3
 - Removed Angular UI Bootstrap, to make the Angular update possible without
   updating Bootstrap
 - Moved every view into its own module
 - Added concatenation of the module js and css assets to the webserver
 - Created directives/components for the various visual components and trimmed
   down the controllers
 - Removed unecessary ngRoute
 - Removed classpath section in details (it is included in environment)
 - Moved the counters and gauges to a separated metrics view
 - Added target="_blank" for the logfile
 - Added information about version, loaded ui modules to the about page
 - Extracted the activiti view to a separate maven artifact

With this commit it is now possible to add your own ui modules to the servers
classpath and they will show up in the ui.
Every module needs an "entry" script file in the classpath located under
`META-INF/spring-boot-admin-server-ui/<modulename>/module.js`.
The module is be implemented as angular module and needs to be added to
the global `uiModules` list.
The spring-boot-admin-server-ui-activiti module is a simple sample for
adding a application view but it is also possible to add main-views.
Please have a look at the events module in spring-boot-admin-server-ui/modules.

Please note that the internals of the ui can change anytime.

Cause it was often requested, now the context-path for the admin server is
configurable. This allows to move the admin-ui and endpoints to other http-
paths than "/".
NOTE: I'd still advise not to add the admin to the application you want to
monitor.

Due to our use of @Conditionals on our @Configuration-classes the import must be deferred, so that the classes are processed after all other @Configuration-classes

 * Use @EventListener instead of ApplicationListener-interface
 * Don't inherit ClientApplicationEvent from ApplicationEvent - so JournaledEvent isn't needed anymore
 * added eclipse formatter rules
 * reformatted all files

Remove unecessary dependencies

fixes #105

The mail notification is enabled if a mailSender is present specified via spring.mail.* properties.
On default the mail is sent to root@localhost and the chages from UNKNOWN to UP are ignored.

Added a simple event journal, jorunaling all ClientApplicationEvents using a simple, non-persistent store. So all information is lost after restart. Added corresponding view to UI.

The health-check is made at a fixed interval (default: 10s) for all expired status-information (default-lifetime: 30s).
The application health-endpoint must either respond with a JSON-Body having a status-field or with an empty body and all 2xx-http-responses are interpreted as UP and every other status as DOWN.

fixes #61

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

Rename ApplicationStore methods to spring-data-style

* Separate AppStore from AppRegistry
* Allow Id generation to be altered
* Remove logic from Application; Move id genretation into AppRegistry
* Make AppStore threadSafe

* registry-key is derived from URL
* option to specify a management-URL and other various config options see spring-boot-starter-admin-client/README.md
* less chatty registration
* some more test cases
* show application URL in overview and headline
* show application info in overview
* set HTTP-Codes in RegistryController

fixes #13
fixes #16
closes #17
closes #18

I didn't add the key-value-properties to the Application. Since it was somehow redundant to the /info-endpoint.