write new job splitter for express merges

[hufnagel]

Based on CVS:

T0/src/python/T0/JobSplitting/ExpressMerge.py
T0/src/python/T0/State/Database/Oracle/ListFilesForExpressMerge.py

The old code should not be used as-is, because in the new system we are dealing with subscriptions for only a single dataset, not the one global expressmerge subscriptions.

We still cannot use the standard merge subscription because for express merges we need two special features:

1. latency based merge triggers (based on data arrival or lumi closing)
2. enforcing lumi order without holes

These features are already supported in the current code and the code fragment dealing with them should be usable.

PS: We do not need to support splitting express data into primary datasets during the express merge. That is a feature which is supported by the current Tier0, but which has never been used.

[drsm79]

metson: Milestone T0 2_0_0 deleted

[hufnagel]

hufnagel: Adds ExpressMerge job splitter, data discovery DAO and unit tests. Also restructures the Express and Repack unit tests somewhat (for consistency reasons to stay in sync with the ExpressMerge unit test). Therefore this patch depends on #2481

[hufnagel]

hufnagel: Please review (apply #2481, then apply this one, then test Repack, Express and ExpressMerge unit tests)

[DMWMBot]

mnorman: For Repack_t, references to subscription1 and fileset1 have to be pointed to the master version.

Once that's done all unittests work.

[hufnagel]

hufnagel: Ok, done (and retested the unit tests myself as well), will commit later.

[hufnagel]

hufnagel: (In f3cf6eb) Job splitter for express merges, fixes #1968

Signed-off-by: Dirk Hufnagel Dirk.Hufnagel@cern.ch