Updated codemirror to v4.12.

Did a lot of cleanup to limit the size of the plugin.
I kept the emmet plugin.

applications/admin/static/codemirror/lib/codemirror.css

@@ -5,10 +5,6 @@
   font-family: monospace;
   height: 300px;
 }
-.CodeMirror-scroll {
-  /* Set scrolling behaviour here */
-  overflow: auto;
-}
 
 /* PADDING */
 
@@ -40,6 +36,9 @@
   box-sizing: content-box;
 }
 
+.CodeMirror-guttermarker { color: black; }
+.CodeMirror-guttermarker-subtle { color: #999; }
+
 /* CURSOR */
 
 .CodeMirror div.CodeMirror-cursor {
@@ -49,15 +48,42 @@
 .CodeMirror div.CodeMirror-secondarycursor {
   border-left: 1px solid silver;
 }
-.CodeMirror.cm-keymap-fat-cursor div.CodeMirror-cursor {
+.CodeMirror.cm-fat-cursor div.CodeMirror-cursor {
   width: auto;
   border: 0;
   background: #7e7;
 }
+.CodeMirror.cm-fat-cursor div.CodeMirror-cursors {
+  z-index: 1;
+}
+
+.cm-animate-fat-cursor {
+  width: auto;
+  border: 0;
+  -webkit-animation: blink 1.06s steps(1) infinite;
+  -moz-animation: blink 1.06s steps(1) infinite;
+  animation: blink 1.06s steps(1) infinite;
+}
+@-moz-keyframes blink {
+  0% { background: #7e7; }
+  50% { background: none; }
+  100% { background: #7e7; }
+}
+@-webkit-keyframes blink {
+  0% { background: #7e7; }
+  50% { background: none; }
+  100% { background: #7e7; }
+}
+@keyframes blink {
+  0% { background: #7e7; }
+  50% { background: none; }
+  100% { background: #7e7; }
+}
+
 /* Can style cursor different in overwrite (non-insert) mode */
 div.CodeMirror-overwrite div.CodeMirror-cursor {}
 
-.cm-tab { display: inline-block; }
+.cm-tab { display: inline-block; text-decoration: inherit; }
 
 .CodeMirror-ruler {
   border-left: 1px solid #ccc;
@@ -70,11 +96,12 @@ div.CodeMirror-overwrite div.CodeMirror-cursor {}
 .cm-s-default .cm-atom {color: #219;}
 .cm-s-default .cm-number {color: #164;}
 .cm-s-default .cm-def {color: #00f;}
-.cm-s-default .cm-variable {color: black;}
+.cm-s-default .cm-variable,
+.cm-s-default .cm-punctuation,
+.cm-s-default .cm-property,
+.cm-s-default .cm-operator {}
 .cm-s-default .cm-variable-2 {color: #05a;}
 .cm-s-default .cm-variable-3 {color: #085;}
-.cm-s-default .cm-property {color: black;}
-.cm-s-default .cm-operator {color: black;}
 .cm-s-default .cm-comment {color: #a50;}
 .cm-s-default .cm-string {color: #a11;}
 .cm-s-default .cm-string-2 {color: #f50;}
@@ -94,12 +121,16 @@ div.CodeMirror-overwrite div.CodeMirror-cursor {}
 .cm-header, .cm-strong {font-weight: bold;}
 .cm-em {font-style: italic;}
 .cm-link {text-decoration: underline;}
+.cm-strikethrough {text-decoration: line-through;}
 
 .cm-s-default .cm-error {color: #f00;}
 .cm-invalidchar {color: #f00;}
 
+/* Default styles for common addons */
+
 div.CodeMirror span.CodeMirror-matchingbracket {color: #0f0;}
 div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
+.CodeMirror-matchingtag { background: rgba(255, 150, 0, .3); }
 .CodeMirror-activeline-background {background: #e8f2ff;}
 
 /* STOP */
@@ -116,6 +147,7 @@ div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
 }
 
 .CodeMirror-scroll {
+  overflow: scroll !important; /* Things will break if this is overridden */
   /* 30px is the magic margin used to hide the element's real scrollbars */
   /* See overflow: hidden in .CodeMirror */
   margin-bottom: -30px; margin-right: -30px;
@@ -160,7 +192,6 @@ div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
 
 .CodeMirror-gutters {
   position: absolute; left: 0; top: 0;
-  padding-bottom: 30px;
   z-index: 3;
 }
 .CodeMirror-gutter {
@@ -168,13 +199,17 @@ div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
   height: 100%;
   -moz-box-sizing: content-box;
   box-sizing: content-box;
-  padding-bottom: 30px;
-  margin-bottom: -32px;
   display: inline-block;
+  margin-bottom: -30px;
   /* Hack to make IE7 behave */
   *zoom:1;
   *display:inline;
 }
+.CodeMirror-gutter-wrapper {
+  position: absolute;
+  z-index: 4;
+  height: 100%;
+}
 .CodeMirror-gutter-elt {
   position: absolute;
   cursor: default;
@@ -183,6 +218,7 @@ div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
 
 .CodeMirror-lines {
   cursor: text;
+  min-height: 1px; /* prevents collapsing before first draw */
 }
 .CodeMirror pre {
   /* Reset some styles that the rest of the page might have set */
@@ -220,10 +256,6 @@ div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
 
 .CodeMirror-widget {}
 
-.CodeMirror-wrap .CodeMirror-scroll {
-  overflow-x: hidden;
-}
-
 .CodeMirror-measure {
   position: absolute;
   width: 100%;
@@ -242,7 +274,7 @@ div.CodeMirror span.CodeMirror-nonmatchingbracket {color: #f22;}
 div.CodeMirror-cursors {
   visibility: hidden;
   position: relative;
-  z-index: 1;
+  z-index: 3;
 }
 .CodeMirror-focused div.CodeMirror-cursors {
   visibility: visible;
@@ -250,6 +282,7 @@ div.CodeMirror-cursors {
 
 .CodeMirror-selected { background: #d9d9d9; }
 .CodeMirror-focused .CodeMirror-selected { background: #d7d4f0; }
+.CodeMirror-crosshair { cursor: crosshair; }
 
 .cm-searching {
   background: #ffa;
@@ -268,3 +301,9 @@ div.CodeMirror-cursors {
     visibility: hidden;
   }
 }
+
+/* See issue #2901 */
+.cm-tab-wrap-hack:after { content: ''; }
+
+/* Help users use markselection to safely style text background */
+span.CodeMirror-selectedtext { background: none; }