Hardening/619 forbidden characters

### Description
o The response to 'Service not found: $URL' changed to 'unrecognized request', to avoid to respond with the data that the user supplied (security risk)
o Requests with any of the 'forbidden characters' in the values of the payload (see issue #619) are refused, both for XML and JSON.

When testing the functional tests, the test that puts a '>' in the middle of a value of the payload made the 'entityId' function not called during the parse step. This has the consequence that reqDataP->dcar.entityIdP is never allocated (it is still NULL) and we bot a nice little SIGSEGV,
To fix this problem, the checks for "reqDataP->xxxx.entityIdP != NULL)" have been implemented.

So, while the fix has nothing to do with this PR, the fix was necessary for the func tests of this PR to work.