Community Edition 4.2.8-rc3 Release Candidate 3

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
HPCC-10735 Support different query classes in the regression suite

Rebase to latest 5.0.x

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
HPCC-10142 queryLogicalFilename not supported on hthor (or Roxie)

Add code to keep logical filename.
Add regression test

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
HPCC-10142 queryLogicalFilename not supported on hthor

Refactor the code
    - Separate the superfile processing and use nested iterators
    - Separate single file processing
    - Remove leading '~' char from logical file name.

Tested with issue10142.ecl

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>