option to disable forms

[ami]

(and other forms, once we support those)

pending #256

[itsjavi]

+1 I think it would help to have toggles for Show/hide forms, also a view for listing only the forms and another for listing only the main default species.

[DaanVandenBosch]

I would like to have a toggle per pokemon if possible. Because I collect all the different forms but also the differing genders. But people have different opinions about what constitutes a big enough difference. E.g. wobbuffet with the red lipstick on the female version.

Having buttons to toggle the following en masse would be useful though:

• show/hide genders
• show/hide forms
• show/hide alolan forms
• show/hide forms that can't be moved to pokemon bank
• show/hide genders with differences

[QuirkyRabbit]

Please I just want to remove the Gigantamax mons from the list, it annoys me that regardless of whether or not I have them marked, the count and the percentage are inaccurate either way