A few doc changes, added emptyText, reorganized haddock order for combinators.
A few doc changes, added emptyText, reorganized haddock order for combinators.

Soostone/blaze-html-haste,jgm/blaze-html,jgm/blaze-html,mikehat/blaze-all,FranklinChen/blaze-markup,Soostone/blaze-markup-haste,Soostone/blaze-markup-haste,iblech/blaze-html,iblech/blaze-html,mikehat/blaze-all,dylex/blaze-markup,mikehat/blaze-all,dylex/blaze-markup,FranklinChen/blaze-markup,jgm/blaze-html