Merge pull request #1851 from rybak/monospace-disable-ligatures

css: disable ligatures in monospace fonts

This guarantees that `<pre>`-formatted text's character widths match viewers' expectations.

app/assets/stylesheets/application.scss

@@ -39,6 +39,7 @@ pre {
   color: $orange;
   display: block;
   font-family: $fixed-width-font-family;
+  font-variant-ligatures: none;
   line-height: 18px;
   margin-bottom: 1em;
   overflow: auto;

app/assets/stylesheets/man-pages.scss

@@ -6,6 +6,7 @@
   p {
     em {
       font-family: $fixed-width-font-family !important;
+      font-variant-ligatures: none;
       font-style: normal;
       font-weight: bold;
       color: $fixed-width-font-color;
@@ -28,6 +29,7 @@
       display: block;
       padding: 2px;
       font-family: $fixed-width-font-family !important;
+      font-variant-ligatures: none;
       background-color: #eee0b5;
     }
     margin-bottom: 15px;
@@ -35,6 +37,7 @@
 
   dt.hdlist1 {
     font-family: $fixed-width-font-family !important;
+    font-variant-ligatures: none;
   }
 
   // Man pages
@@ -44,6 +47,7 @@
       margin-bottom: 1em;
       font-family: $fixed-width-font-family !important;
       line-height: $fixed-width-line-height;
+      font-variant-ligatures: none;
       color: $fixed-width-font-color;
       word-wrap: break-word;       /* Internet Explorer 5.5+ */
       white-space: pre;

app/assets/stylesheets/typography.scss

@@ -258,6 +258,7 @@ code {
   overflow: auto;
   font-family: $fixed-width-font-family;
   line-height: $fixed-width-line-height;
+  font-variant-ligatures: none;
   color: $orange;
   background-color: #fff;
   border: solid 1px #efeee6;
@@ -364,6 +365,7 @@ div.more {
 
 .fixed {
   font-family: $fixed-width-font-family;
+  font-variant-ligatures: none;
 }
 
 .text-center {