[3.1] DUNE: adds passing arguments to programs (CMake, gdb, and ctest)

[linh2931]

Resolved VaultaFoundation#10.

Arguments of programs like CMake, gdb, and ctest are introduced using --, after DUNE's own arguments.

A section of DUNE's help look like

...
dune -h
  --cmake-build ['DIR', '-- FLAGS (Optional)']
                        build a smart contract project at the directory given
                        optional flags are of the form -- -DFLAG1=On
                        -DFLAG2=Off]
  --ctest ['DIR', '-- FLAGS (Optional)']
                        run the ctest tests for a smart contract project at
                        the directory given optional flags are of the form --
                        -VV
  --gdb ['DIR', '-- FLAGS (Optional)']
                        run the ctest tests for a smart contract project at
                        the directory given optional flags are of the form --
                        -VV
...

A sample run of gdb with argument -c core-file looks like

dune --gdb ./src -- -c core-file
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/host/home/lh/work/dune/src: No such file or directory.
/app/core-file: No such file or directory.