Cli landing page (#78)

* Add rust-toolchain file

No idea what tool the RustConfig file is for, but this one works with
rustup (which I hear is quite popular ;))

* Update CLI entry page with some nicer content

* Address review feedback

- Code in partials
- Less CSS noise

* Adding some preliminary icons that have been modified from their upstream counterparts

* Add/Rename CLI Icons for Great Justice

* Add Some Icons to CLI Landing Page

* CLI Pitch Boxes

* CLI: Mo Boxes, Mo Content

* Changing icon colours to white background and decreasing opacity

* Making the initial pitch icons also white and tweaking the CSS to match

* Adding initial texts to most of the detail boxes

* Changing exit-codes svg from $? to arrow

* Fixing the CLI icon colour

* CLI: White buttons pls

* CLI: Links, Three More Sections

* CLI: Line breaks and code

* Cli: Trim title

* CLI: Last but not least

* this would require to much updating

Author: killercup

src/styles/app.scss

@@ -90,7 +90,8 @@ span.brand img {
 .domains h3, #whitepapers h3, #using-the-trademarks h3,
 #contribute-code h3, #contribute-talk h3, #contribute h3,
 #community-events h3, #tools-code-quality h3, #learn-use h3,
-#embedded-why-rust h3, #embedded-get-started h3 {
+#embedded-why-rust h3, #embedded-get-started h3,
+#cli-features h3, #cli-pitch h3 {
   font-weight: 800; 
   font-size: 1.8em;
 }
@@ -560,6 +561,63 @@ blockquote::before {
   }
 }
 
+#cli-pitch,
+#cli-features {
+  .domain-icon {
+    display: block;
+    padding-bottom: 0;
+
+    img {
+      max-width: 90px;
+      height: auto;
+      display: block;
+      margin-left: auto;
+      margin-right: auto;
+      padding-bottom: 1em;
+      opacity: 0.9;
+    }
+  }
+}
+
+#cli-pitch {
+  background-color: $green;
+  color: white;
+  
+  .button-secondary {
+    border-color: #fff;
+  }
+  
+  a {
+    color: #fff;
+    text-decoration: none;
+  }
+}
+
+#cli-features {
+  background-color: $red;
+  color: white;
+
+  a {
+    color: $yellow;
+  }
+  
+  h3 code {
+    background-color: transparent;
+    border: none;
+    word-break: break-word;
+    white-space: pre-line;
+  }
+}
+
+#cli-use-it {
+  background-color: $purple;
+  color: white;
+  
+  pre {
+    color: black;
+  }
+}
+
 #ferris-error {
   width: 80%;
 }