Continuing work on expressions (AliceO2Group#2563)

* Reworked tree-parsing algorithm to use ArrowDatumSpec
* Added a test of tree-parsing algorithm

DPL: optimize ContextRegistry lookup (AliceO2Group#2562)

Now it does the hash calculation at compile time and it uses fast
hash table to do the lookup.

Update ANALYSIS.md (AliceO2Group#2564)

Small improvements

Make FMQ transport tests use unique id for sessions (AliceO2Group#2550)

DPL Analysis: add operator+ and operator- to RowView (AliceO2Group#2551)

Simplifies writing correlation loops.

DPL: fix quit logic in test_DanglingOutputs (AliceO2Group#2548)

Commandline option to limit number of events given by the run2ESDCove…

…rter (AliceO2Group#2543)

* Use "--event=100000 --esd-file=AliESDs.root"

GPU: Cosmetics, get rid of _ after each kernel name

Elininate cluster mROFrame and its usage