Reset of section numbering for Sociology Short Answer EOC questions

For the Sociology text, created a separate numbering.less file (sociology-numbering.less) to reset section numbering for the Short Answer eoc section.  Other books utilize sequential numbering of eoc questions.  This Sociology section is an exception.  Creation of new file to sidestep changing numbering.less again and addition of per-book code into that file.  Comments added for future refactoring numbering schema to take this into account.