Fix class name in a comment

(cherry picked from commit fc7ad8ec85ac3cd6fb9596e3eedeac370ff78c79)
WICKET-4703 StringResourceModel should provide an overridable getString(Component) method

Make StringResourceModel#getString(Component) overridable

(cherry picked from commit 1a5551273396d3babb79146b23e4d3afd42da3e8)
Library updates

Jetty: 9.2.6
Log4j: 2.1.0
JUnit: 4.12
Mockito: 1.10.16
SLF4J: 1.7.8
WICKET-5776 Add information about the component when it fail in detach phase

try/catch the application related logic in Component#detach()

(cherry picked from commit 39b65ecf1ce4a3904227a9dbdec9f8ca874f8a7e)