Refactor intro

<h3>Summary<h3/>
+ restructured .LESS files in congruence with .LESS specification and coding standards (comments, imports, mixin, variables, code blocks)
+ grouped and restructured book toc rules in base
+ rewrote book specific styles
<h4>Testing<h4/>
+ Anatomy: http://naginata.cnx.rice.edu:9090/content/col10010/latest/pdf
+ Biology: http://naginata.cnx.rice.edu:9090/content/col10001/latest/pdf
+ Biology NonMajors: http://naginata.cnx.rice.edu:9090/content/col10006/latest/pdf
+  Physics: http://naginata.cnx.rice.edu:9090/content/col10003/latest/pdf
+ Sociology: http://naginata.cnx.rice.edu:9090/content/col10004/latest/pdf

<h4>Additional Testing Results for Review (regression)<h4/>
+ Control PDF's: http://mountainbunker.org/~jburnett/refactor_controls
+ Result PDF's: http://mountainbunker.org/~jburnett/refactor_results