Fix action input to allow for themes that change button padding

src/definitions/elements/input.less

@@ -365,6 +365,8 @@
   display: table-cell;
   vertical-align: middle;
   white-space: nowrap;
+  padding-top: @verticalPadding;
+  padding-bottom: @verticalPadding;
 }
 .ui.action.input > .button > .icon,
 .ui.action.input > .buttons > .button > .icon {

src/themes/raised/elements/button.variables

@@ -10,6 +10,7 @@
 @backgroundImage: linear-gradient(transparent, rgba(0, 0, 0, 0.05));
 @verticalAlign: middle;
 @borderRadius: 0.4em;
+@borderBoxShadowColor: @borderColor;
 
 /* Shadow */
 @shadowDistance: 0.3em;