Add pee

[MDLC01]

The idea of adding U+2118 ℘ SCRIPT CAPITAL P (with Unicode normative alias WEIERSTRASS ELLIPTIC FUNCTION) has been floating around for a while. To be clear, this is not the same as cal(P) or scr(P). This is a different symbol, akin to ell. Quoting UTR #25 (Section 2.3):

The two characters U+2113 ℓ SCRIPT SMALL L, and U+2118 ℘ SCRIPT CAPITAL P, are not regular script characters, despite their character names.

The name pee is a bit unfortunate, but it is consistent with ell. For this reason, I will wait for an approval from @laurmaedje before merging this.

[Enivex]

I'll add my message on discord here:

If this isn't an acceptable name, there's pea. It's less natural, but at least doesn't have the unfortunate alternate meaning

[MDLC01]

I updated the changelog as well