fixed return type for columns/rows dot_prod and dot_self in manual
Print BFGS output header every 50*refresh iterations.
Merge branch 'master' of https://github.com/stan-dev/stan
Merge branch 'master' of https://github.com/stan-dev/stan
updated includes for rev/assign_to_var
added assign_to_var for fvar/matrix
Correct specification of ogita algorithm
Merge branch 'master' into kahanSum