reorganize tests, with clean workspace and repeatability

using WorkspaceTest as base class for tests
restrict exported guava packages
small fix in ErlParser
pathVars: use project's resolver

this allows using predefined vars like PROJECT_LOC
cleanup OtpRpcFactory
removed unused OpenService.getExternalInclude
merge ModelSearcherService into ModelFindService
extract Util.asStringList
small fixes
code cleanup
fix dependency
extract library properties from project properties
introduce projectProperties.libraries
introduce project properties helper, to handle external libraries
wip