Job control rewrite

[lmorg]

This PR relates to the following Github Issue: https://github.com/lmorg/murex/issues/863

Please follow that thread for updates rather than this PR

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 29.39439% with 478 lines in your changes missing coverage. Please review.

Please upload report for BASE (develop@ef4167b). Learn more about missing BASE report. Report is 108 commits behind head on develop.

Files with missing lines	Patch %	Lines
shell/signal_handler/sigfns/sigfns_unix.go	0.00%	107 Missing :warning:
lang/exec_unix.go	0.00%	53 Missing :warning:
shell/signal_handler/sigfns/sigfns.go	0.00%	46 Missing :warning:
builtins/core/lists/regexp_functions.go	50.00%	28 Missing and 13 partials :warning:
shell/session/session_unix.go	0.00%	38 Missing :warning:
lang/exec.go	23.68%	25 Missing and 4 partials :warning:
shell/signal_handler/signals_unix.go	36.66%	17 Missing and 2 partials :warning:
builtins/core/lists/match.go	44.82%	11 Missing and 5 partials :warning:
builtins/core/lists/regexp_params.go	68.18%	12 Missing and 2 partials :warning:
lang/process/sysproc.go	74.54%	14 Missing :warning:
... and 17 more

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #865 +/- ## ========================================== Coverage ? 42.31% ========================================== Files ? 550 Lines ? 36982 Branches ? 0 ========================================== Hits ? 15648 Misses ? 20014 Partials ? 1320 ```

:umbrella: View full report in Codecov by Sentry.
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[sonarcloud[bot]]

Quality Gate passed

Issues
8 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud