Sort emblems by 'difficulty' rating about mtg-emblems

[FM-96]

Good idea!

[pgrosslicht]

The 'difficulty' rating is kind of implemented in that there is now a field called 'difficulty' in embleme_list.coffee. I've added it in 2f4f229, we now just have to really set the 'difficulty'.

I propose the following legend:
0 - easy
1 - normal
2 - hard
3 - Uber

[FM-96]

Legend sounds good, but by what criteria are we differentiating?

[pgrosslicht]

Potency of the emblems. Emblems that can turn the game in one turn should at least be hard, for example. Emblems that are only stalling would be easy.

[FM-96]

Should we maybe initially set all difficulties to (for example) -1 for "not yet rated"?

...or, actually, just define 0 as "not yet rated" and make the difficulties 1 to 4.

[pgrosslicht]

I guess defining 0 as "not yet rated" is easier. So new legend:

0 - not yet rated
1 - easy
2 - normal
3 - hard
4 - Uber