Major refactor and rename of feature

All forward facing wording changed to Export to Git
Export to git functions removed from management command and put in common file
Additional error checking and documentation improvements
Nitpicks and other minor fixes

cms/static/sass/style-app-extend1.scss

@@ -44,7 +44,7 @@
 @import 'views/users';
 @import 'views/checklists';
 @import 'views/textbooks';
-@import 'views/push';
+@import 'views/export-git';
 
 // base - contexts
 @import 'contexts/ie'; // ie-specific rules (mostly for known/older bugs)

cms/static/sass/views/_export-git.scss

@@ -1,7 +1,7 @@
-// studio - views - push to lms
+// studio - views - export to git
 // ====================
 
-.view-push {
+.view-export-git {
 
   // UI: basic layout
   .content-primary, .content-supplementary {
@@ -24,24 +24,24 @@
 
   h3 {
       font-size: 19px;
-      font-weight: 700;    
+      font-weight: 700;
   }
 
-  .push-info-block {
+  .export-git-info-block {
 
     dt {
       font-size: 19px;
       font-weight: 700;
-	  margin-top: 12px;
+      margin-top: 12px;
     }
 
     dd {
       font-size: 17px;
-	  margin-bottom: 20px;
+      margin-bottom: 20px;
     }
-	
+
     .course_text {
-		color: $green;
+        color: $green;
     }
     .giturl_text {
       color: $blue;
@@ -57,7 +57,7 @@
   }
 
  // UI: export controls
-  .push-controls {
+  .export-git-controls {
     @include box-sizing(border-box);
     @extend %ui-window;
     padding: $baseline ($baseline*1.5) ($baseline*1.5) ($baseline*1.5);
@@ -66,7 +66,7 @@
       @extend %t-title4;
     }
 
-    .action-push {
+    .action-export-git {
       @extend %btn-primary-blue;
       @extend %t-action1;
       display: block;
@@ -87,7 +87,6 @@
         display: inline-block;
         vertical-align: middle;
       }
-	}
+    }
   }
 }
-