moves current_user back into application helper
changes added as per abi's comments

this adds, flash.now (which is used when you do a render instead of a
redirect)

this also removes the parens

this additionally adds a comment where someone needs to explain why we
aren't just looking up the current user with our helper
adds flash.now so that it will show up on render
changes inject to sql sum
removes whitespace and let! where appropriate
Merge pull request #21 from zachgersh/code_review_changes

Code review changes