✨ mgm-hurry - Implement custom search space values

[Rikj000]

With MoniGoMani growing in size, I think it can be beneficial / give us more control if we implement custom search space values.

For example:

• Add an unclogger unclogger space for mgm-hurry
• Which will allow us to specify if we seek to optimize the unclogger by passing
• Or if we simply wish use it without optimization during our HyperOpt process.

In the underlying code not much has to change, the unclogger just will stay inside the freqtrade sell space,
but it would be nicer/more clear to the users like that I think. While also giving us more control over our HyperOpts.

I'm already thinking about following new mgm-hurry specific optimizable search spaces:

• unclogger
• weighted_triggers
• weighted_guards
• (Or without @raftersvk's changes simply weighted_signals)
• weighted_crosses (To be implemented)