Iterative grid search

[h-0-0]

Would be nice to have an iterative grid searcher, I think the best way to implement this would be for it to default to regular grid search if there are no existing results (this information will be given to the searcher through a saver). If there are existing results then it defines a grid search based on the results.

For example, if the best results are for parameters at the edge of the grid then the new grid should focus on values that are more extreme. If the best results lie within some sub-grid then we should define a finer grid search in that area.

Will have to manually define the iterative grid and 'sbatchit' each time you want to conduct a new grid search based on the previous searches. However, in the future you may be able to monitor the job status and automatically submit the next grid search when this functionality is added to slune.