Improve logging of homotopy-based initialization (-ils)

[Francesco Casella]

The current implementation of the homotopy-based initialization produces the following log, when turning on LOG_NLS:

LOG_INIT          | info    | homotopy process
...
LOG_INIT          | info    | | lambda = 0 done
...
LOG_INIT          | info    | | lambda = 0.1 done
...
...
LOG_INIT          | info    | | lambda = 1 done

IMHO this is a bit confusing, and also a bit awkward to search for in huge log files. I would propose to change the logging to get the following output

LOG_INIT          | info    | homotopy process
LOG_INIT          | info    | ---------------------------
LOG_INIT          | info    | | homotopy parameter lambda = 0
...
LOG_INIT          | info    | | homotopy parameter lambda = 0 done
LOG_INIT          | info    | ---------------------------
LOG_INIT          | info    | | homotopy parameter lambda = 0.1
...
LOG_INIT          | info    | | homotopy parameter lambda = 0.1 done
LOG_INIT          | info    | ---------------------------
...
...
LOG_INIT          | info    | | homotopy parameter lambda = 1 done

This would make the debug log much easier to search and interpret.

[Lennart Ochel]

​OMCompiler#1385 changes the dump to the following output:

LOG_INIT          | info    | homotopy process
|                 | |       | ---------------------------
LOG_INIT          | info    | homotopy parameter lambda = 0
...
LOG_INIT          | info    | homotopy parameter lambda = 0 done
|                 | |       | ---------------------------
LOG_INIT          | info    | homotopy parameter lambda = 0.0526316
...
LOG_INIT          | info    | homotopy parameter lambda = 0.0526316 done
|                 | |       | ---------------------------