obshashrange: use the dualsourcecache as a base for the cache This will easily open the way to incrementally updated obshashrange cache. Small update are needed to the data base schema so be bump the version Currently the update function is not warming the cache (but details case where it is invalidated).

syntax: re
/figures/[^/]+\.png$
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^tests/easy_run.sh$
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tests/\.testtimes