SWITCHYARD-1735 fix editor synchronization issues with problem markers

https://issues.jboss.org/browse/SWITCHYARD-1735

Also fixed some minor issues found while testing validation.
 * java interface browse is now constrained to the project classpath
 * added adapter for resolving transformer files (e.g. smooks xml, xslt, etc.), which are added as dependencies for the validator (i.e. when these files change, it prompts a validation of switchyard.xml).