buttons and icons updated for improved placement and variable support for icon paths

less/buttons.less

@@ -76,7 +76,7 @@
   line-height: normal;
   .border-radius(5px);
 }
-.btn-large .icon {
+.btn-large [class^="icon-"] {
   margin-top: 1px;
 }
 
@@ -86,7 +86,7 @@
   font-size: @baseFontSize - 2px;
   line-height: @baseLineHeight - 2px;
 }
-.btn-small .icon {
+.btn-small [class^="icon-"] {
   margin-top: -1px;
 }
 

less/sprites.less

@@ -18,15 +18,16 @@
   display: inline-block;
   width: 14px;
   height: 14px;
+  line-height: 14px;
   vertical-align: text-top;
-  background-image: url(../img/glyphicons-halflings.png);
+  background-image: url(@iconSpritePath);
   background-position: 14px 14px;
   background-repeat: no-repeat;
 
   .ie7-restore-right-whitespace();
 }
 .icon-white {
-  background-image: url(../img/glyphicons-halflings-white.png);
+  background-image: url(@iconWhiteSpritePath);
 }
 
 .icon-glass              { background-position: 0      0; }

less/variables.less

@@ -47,15 +47,19 @@
 // Z-index master list
 // Used for a bird's eye view of components dependent on the z-axis
 // Try to avoid customizing these :)
-@zindexDropdown:        1000;
-@zindexPopover:         1010;
-@zindexTooltip:         1020;
-@zindexFixedNavbar:     1030;
-@zindexModalBackdrop:   1040;
-@zindexModal:           1050;
+@zindexDropdown:          1000;
+@zindexPopover:           1010;
+@zindexTooltip:           1020;
+@zindexFixedNavbar:       1030;
+@zindexModalBackdrop:     1040;
+@zindexModal:             1050;
+
+// Sprite icons path
+@iconSpritePath:          "../img/glyphicons-halflings.png";
+@iconWhiteSpritePath:     "../img/glyphicons-halflings-white.png";
 
 // Input placeholder text color
-@placeholderText:       @grayLight;
+@placeholderText:         @grayLight;
 
 // Navbar
 @navbarHeight:                    40px;