Revision 1762227

Improved: cleanups and enhancements in the FreeMarkerWorker class, and client 
code using it, that wraps most of the OFBiz integration with FreeMarker.

This is the list of the main modifications:
* simplified and cleaned up the public methods of FreeMarkerWorker, used to 
retrieve and render Freemarker templates and changed client code accordingly to 
use them
* removed unused methods in FreeMarkerWorker and made some others private
* improved the integration code in FreeMarkerWorker to better use the Freemarker 
API and specifically to leverage the various TemplateLoaders and the Freemarker 
caching mechanism; it is now possible to switch the OFBiz legacy template 
caching mechanism to use the Freemarker one instead
* improved the implementation of Freemarker template rendering from strings 
(used by DataResourceWorker): it now leverages the Freemarker's 
StringTemplateLoader that provides the ability to cache the strings, retrieved 
from DataResources records, based on the timestamp of the last modification
* moved freemarkerImports.properties from "widget" to "base" component, and 
changed its content (and the content of the associated templates 
AutoImportTemplate.ftl and HtmlTemplate.ftl) to remove the dependency from base 
to widget&common; some resources of "widget" and "common" are still referenced 
from AutoImportTemplate.ftl (that is in "base") but even if they are soft 
dependencies: if they are missing the system will load properly without any 
error or warning; before this change it was impossible to use, or unit test, 
FreeMarkerWorker before the "widget" and "common" components were loaded by the 
system, now it is possible
* created a new class for unit tests for FreeMarkerWorker, named 
FreeMarkerWorkerTests: at the moment it contains just one simple unit test but 
more should be implemented
* refactored WebToolsServices.entityImport(...) to leverage the 
FreeMarkerWorker.renderTemplate(...) method to run the Freemarker template, 
rather than dealing with the Freemarker API directly; this is now possible 
thanks to the cleanups and improvements done in the FreeMarkerWorker class; this 
same approach should be implemented for a few other similar integration points 
(mostly in the "content" component); this is a TODO item
* moved the encodeDoubleQuotes(...) method from FreeMarkerWorker to 
MacroFormRenderer and made it private since this is the only calss using it and 
its logic is not related to FreeMarker