Refactor `BaseProfile` class

1. The "searchspace_str" has to be removed from the initializer of `BaseProfile`. It's unintuitive.
2. The file name `profile_config.py` is also confusing and needs to be updated.
3. Method `configure_extra` has a different signature compared to the other `configure_` methods.
4. `get_name_wandb_run` -> improve the name. The emphasis should be on the experiment name, not the "wandb name". Perhaps it's better to move this method elsewhere (having it here is what raises the need for searchspace_str in the init). The Experiment class seems like a suitable candidate.
5. The configs in `_initialize_train_config_xyz` are better of as config (yaml?) files which are included with the library, which are read and loaded into the `BaseProfile` class.
6. `set_searchspace_config` should has the same function but as `configure_xyz` but a different naming convention. Rename it.