Add tests on FuchsiaUtils.getFilter()
Add Introspection interfaces for import-chain

Add Introspection interfaces for the components of the import-chain
(ImportationLinker, DiscoveryService and ImporterService).
Update tests using introspection functions
Allow ImporterService to throw ImporterException

Rename BadImportRegistration to ImporterService.
addImporterDeclaration and removeImportDeclaration can now throw
ImporterException.

Handle duplicate ImportDeclaration.
Handle duplicate ImportDeclaration into ADiscovery
Fix in FuchsiaUtilsTest
Correct reconfigure in DefaultImportationLinker

Correctly handle the reconfiguration of the properties Filter_ImportDeclaration
and Filter_ImporterService.
The sets of ImportDeclaration and ImporterService are updated to be consistents
with the new filter.
The update of the Target properties of the ImporterService now update the set of
ImportDeclaration which are binded to them.

Add tests related to theses features in DefaultImportationLinkerTest.
Merge remote-tracking branch 'project_original_master/master'
Change Hashmap to Set in getImportDeclaration