Fix LSA naming

[thehomebrewnerd]

Overrides the get_args_string method to avoid displaying a full user-defined custom corpus in the feature name and instead just displays corpus=user_defined instead.

Also updates the algorithm default value to randomized instead of None to prevent it from always being displayed in feature name.

[dvreed77]

curious if there is a difference doing it this way vs the way it was?

[thehomebrewnerd]

It impacts how the feature names are generated. The way feature naming works, parameter values are only included in the feature name if the value is changed from the default value.

With the previous approach the default value was None and the algorithm was set to "randomzied" inside __init__ meaning that even though randomized was effectively the default value, it would always be displayed in the resulting feature name because randomized wasn't the actual default value in the function signature.

Doing it the new way means that "randomized" is the default value in the function signature, and the algorithm info will only show up in the feature name if it is changed to the non-default of "arpack".

[rwedge]

Looks good