alpine-baselayout shouldn't export PS1

I've got a problem that was answered by my shell FAQ:

''Do not export PS1! (This was agreed upon as suggestion in a discussion between bash, zsh and Korn shell developers.) The feature set of different shells vastly differs and each shell should use its default PS1 or from its startup files.'' http://www.mirbsd.org/mksh-faq.htm

I figured the exported PS1 was due to alpine-baselayout so it could just be fixed in the package if you agree.