The handling of dive site merging changed and therefore the tests
have to be adapted.
1) Dive sites are recognized as identical based on their name.
Therefore, give the dive sites that should be merged the same name.
2) The dive site id of the first imported dive is kept. Thus,
merge and reverse merge produce two different output files.
Create a second file reflecting that fact.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
