The POM and other configuration files have been updated to support a new
execution mode where Cargo is used to execute the backend and NPM to
execute the frontend, both in auto-redeploy mode.

The command to execute the application launching it without watching the
file system was not currently working, as the command used "cargo:start"
closed Tomcat when the construction finished.

This command has been replaced by "cargo:run", that blocks the
construction avoiding Tomcat shut down.

The execution sections of the README.md now include a link to the application
home when it is started using the provided commands.

This commit updates the README.md file to include better and more detailed
descriptions of how to construct and execute the application.

The execution command recommended in README.md has been simplified (no tests are executed now) and made more robust by includen a project cleaning and packaging previous to execution.

A big refactorization has been done in this commit, focused on
simplifying the testing and execution process. The Spring-DbUnit library
has been added to allow the use of DbUnit through annotations in the
test classes. This change has been complemented with two new test
listeners that allow the creation of custom initial contexts and the use
of custom SQL scripts to create and destroy the database tables before
and after the test execution, respectively. In addition, all the tests
are executed now using a HSQLDB database.

The datasource configuration has been pulled out of the project, and now
it must be provided by the container.

The sample classes have been reviewed, refactorized and documented with
JavaDoc.

The POM file has been reworked to ease test and application execution
using maven. The new execution modes are:
	- The default execution includes unit, integration and acceptance (with
Selenium) test execution.
	- No acceptance tests: mvn -P -acceptance-tests-cargo <phase>
	- Run server for manual acceptance tests: mvn
-Dcargo.tomcat.start.skip=true -Dcargo.tomcat.run.skip=false
-DskipTests=true pre-integration-test 
	- Run server with MySQL database: mvn -P
run-tomcat-mysql,-acceptance-tests-cargo -DskipTests=true package
cargo:run