use variablef or wells background-color, update docs for glyphicons license mention, update popovers to remove that thick border and make them look mo betta

less/variables.less

@@ -148,6 +148,11 @@
 @hrBorder:                @grayLighter;
 
 
+// Wells
+// -------------------------
+@wellBackground:                  #f5f5f5;
+
+
 // Navbar
 // -------------------------
 @navbarHeight:                    40px;