Experiments on hashing.
Snapshot before moving to indices in associative-multi.
Merge branch 'devel' into associative_tests
Lookup compiles, deletion planned.
Finish deletion of entries from associative-multi hash.
Remove unused code for associative multi arrays.

If we ever need this, it will be better to copy the code for
associative multi pointer arrays.
Graph tests work again.
Merge branch 'devel' into associative_tests
Fix after merge from devel.
Cleanup resizing of MultiPointerHash
Change edge index. Compiles but does not work yet.
Repair graphs with new edge index.
Take out some diagnostics.
Merge branch 'devel' into associative_tests
Use UNIX line endings in xxhash.
Switch off authentication in relative configuration.