skips incomplete surveys while calculating scores for factor graphs

Tracks incomplete, then reduces the count for calculating averages based on that.
validates presence of class size and updates seeds
eliminates dollar signs in radar graphs
adjusts title of sub factor pages to reflect the factor looked at
adds nav for sub factors and persists logo for users to enable simple navigation

Preference is to have fixed position nav at the top. However, it takes longer to do with JQuery, and in the interest of "making it work" before "making it right," I simplified to a logo on the top left that links to user show page, and links at the bottom for subfactors.
styles graphs by positioning them correctly and making it readable

centers graphs and makes tooltip readable
adds borders to factor graphs
styles center, adds borders, and scales sub factor graphs
partials the subfactor nav into a div and adds to factor#show
word-wraps long labels for sub factors within graph div
adds bottom navigation between factor and sub factors to enable that flow