fix(icon): vertical position for unsized icons and sized text

This PR corrects/partly reverts the vertical alignment of unsized icons which unfortunately breaks the vertical alignment in most cases when icons are just used beside inline texts which is probably the most used case.
I also recognized the text element needs the same line-height setting to avoid overlapping which is also fixed now.

Author: lubber-de

src/definitions/elements/icon.less

@@ -288,15 +288,15 @@ each(@colors, {
 i.icon,
 i.icons {
   font-size: @medium;
-  line-height: 1;
-  vertical-align: middle;
+  line-height: @lineHeight;
 }
 & when not (@variationIconSizes = false) {
   each(@variationIconSizes, {
     @s: @@value;
     i.@{value}.@{value}.@{value}.icon,
     i.@{value}.@{value}.@{value}.icons {
       font-size: @s;
+      vertical-align: middle;
     }
   })
 }

src/definitions/elements/text.less

@@ -22,6 +22,9 @@
 /*******************************
              Text
 *******************************/
+span.ui.text {
+  line-height: @lineHeight;
+}
 
 each(@colors, {
   @color: replace(@key, '@', '');

src/themes/default/elements/icon.variables

@@ -53,6 +53,7 @@
 @width: @iconWidth;
 @height: 1em;
 @distanceFromText: 0.25rem;
+@lineHeight: 1;
 
 
 /* Variations */

src/themes/default/elements/text.variables

@@ -5,6 +5,8 @@
 /*-------------------
        Element
 --------------------*/
+@lineHeight: 1;
+
 @mini: 0.4em;
 @tiny: 0.5em;
 @small: 0.75em;