Update shields.md

Corrected Numbering in the MakerKit Section.
Fix scrolling for Firefox
removed unused Libraries heading since Servo started a new one
Merge pull request #79 from dwaq/patch-1

removed unused Libraries heading since Servo started a new one
Merge pull request #67 from ymilord/patch-2

Update shields.md
Fixed thermistor numbering
Merge pull request #78 from KevinGrandon/fix_docs_firefox

Fix scrolling for Firefox
Merge branch 'master' into gh-pages