[Fix #1611] Add an entry for Helm help buffer in display-buffer-alist
[Fix #1611] Add an entry for Helm help buffer in display-buffer-alist

When a Helm help buffer is detected, we don't treat it like other Helm
buffers by simply adding its own entry in display-buffer-alist that does
no additional action.

tsonntag/dotemacs,tsonntag/dotemacs,tsonntag/dotemacs,tsonntag/dotemacs