Revert "re-add conservancy donation banner"
Revert "re-add conservancy donation banner"

This reverts commit 4e43690b60269901fc6c0b0d8139deccb13546f2.

The banner was meant to be up through the new year, which
happened.

Mokolea/git-scm.com,mosoft521/gitscm-next,mosoft521/gitscm-next,jasonlong/git-scm.com,Mokolea/git-scm.com,jasonlong/git-scm.com,git/git-scm.com,jasonlong/git-scm.com,git/git-scm.com,Mokolea/git-scm.com,jasonlong/git-scm.com,mosoft521/gitscm-next,git/git-scm.com,mosoft521/gitscm-next,git/git-scm.com,Mokolea/git-scm.com