Git Clone btn more apparent

Added a faint background to the button to show that it is in an
active state for the user. White background is often hard to tell
if something is being pushed, so adding a "shadow" makes it a bit
easier to tell. Fixes #1998

app/assets/stylesheets/sections/projects.scss

@@ -111,6 +111,8 @@
     color: $link_color;
 
     &.active {
+      background-color: #f5f5f5;
+      border: 1px solid rgba(0,0,0,0.195);
       color: #333;
       font-weight: bold;
     }