Feature/improve cli

[maartenflippo]

Some small tweaks to make the solver more compatible with MiniZinc, as well as be more polished.

• Rename -s to -r for the seed (it should be -r according to https://www.minizinc.org/doc-2.5.5/en/fzn-spec.html#command-line-interface-and-standard-options)
• Add a default timeout if none was specified, which is set to 30 seconds (this is an arbitrary choice, if there are comments on this let me know).
• Add an option to run without a timeout. This is useful when the solver is run with the debugger enabled, because sitting at a breakpoint still advances time. However, in this situation you are not likely to want to timeout.
• In case of a satisfaction problem, stop the solver after the first solution is found.

[maartenflippo]

Added the printing of the appropriate end marker, as specified by https://www.minizinc.org/doc-2.5.5/en/fzn-spec.html#solution-output.

[maartenflippo]

Last feature is the printing of what neighbourhoods are set up.