Should Template runtime dependencies be provided by wcomponents-core

[jonathanaustin]

If projects want to use a handlebars template the project needs to add the slf4j dependency as the handlebars rendering engine requires it at runtime. This is currently provided in the wcomponents-bundle module.

This is related to issue #1756 that projects using templates (velocity or handlebars) also require a JSR107 dependency (eg ehcache). Again this is provided in the wcomponents-bundle module.

Should these extra dependencies be included in wcomponents-core so projects are not required to add any new dependencies when using WTemplate.