Start embedded jetty before running End2End tests

[ikostenko]

No description provided.

[aliubunia]

For some reason Jetty8x embedded container in Cargo does not properly register JSTL namespaces/libs. Thus in this mode the demo app is not functional. Further investigation on the classpath issue needed.

Meanwhile, the application is started in a standalone container.

Assemble the demo app, and then run the functional tests from the module lightadmin-tests with:

mvn verify

[ikostenko]

It turned out that it would be more effective to have two modes of running tests:

1. Developer mode: automatically starting the application before running tests (to run the tests against the recent changes in the application code)
2. Tester mode: starting tests independently of the application (when developing automated tests, the application is usually already running on background)

Currently, only mode # 1 is supported :(

[aliubunia]

Added support for distinct dev and test modes.
The dev mode is applied by default.
The test mode can be activated as follows:

mvn -Dmode=test verify

[ikostenko]

verified