www/py-formalchemy: update to 1.5.5

• switch from GH to CHEESHOP [1]
• convert all build dependencies to run dependencies [1]
• add run dependency on www/py-webob [2]
• add NO_ARCH [3]

PR: 215583 [1]
Submitted by: rene via mail from koobs [1]
Submitted by: maintainer (ghostonthewire@gmail.com) [2]
Submitted by: rene [3]