Updated README with the Dandelion-Datatables configuration file

Upgraded Dandelion-Datatables to the latest release (v0.10.0)

 * The old datatables-servlet2 dependency has been removed from the pom.xml
 * Some attributes have been renamed (e.g. paginate => pageable)
 * Starting from the v0.10.0, all web components (servlet, filter) must be explicitely declared in the web.xml file. That's why I added the following declaration: DandelionFilter, DandelionServlet and DatatablesFilter
 * Added a new datatables.properties file in order to disable the asset management brought by Dandelion-Core. This is equivalent to the old cdn=true table attribute

Remove public to methods from the ClinicService

Fixes #37 with other default locale than english

Any method you define in an interface is by definition public

Test in error with french default Locale:
org.junit.ComparisonFailure: expected:<[ne peut pas être vide]> but was:<[may not be empty]>
	at org.junit.Assert.assertEquals(Assert.java:115)
	at org.junit.Assert.assertEquals(Assert.java:144)
	at org.springframework.samples.petclinic.model.ValidatorTests.emptyFirstName(ValidatorTests.java:39)

adding explicit reference to default profile because it doesn't seem to work on on some environments