Add line diff decorations to editor gutter

Added, modified, and deleted lines will now highlighted
in the gutter for files already checked in to the repository.

src/app/git.coffee

@@ -123,7 +123,7 @@ class Git
         @statusTask = null
       @statusTask.start()
 
-  getDirectoryStatus: (directoryPath) ->
+  getDirectoryStatus: (directoryPath)  ->
     directoryPath = "#{directoryPath}/"
     directoryStatus = 0
     for path, status of @statuses
@@ -133,5 +133,8 @@ class Git
   getAheadBehindCounts: ->
     @getRepo().getAheadBehindCount()
 
+  getLineDiffs: (path, text) ->
+    @getRepo().getLineDiffs(@relativize(path), text)
+
 _.extend Git.prototype, Subscriber
 _.extend Git.prototype, EventEmitter

src/app/gutter.coffee

@@ -76,7 +76,7 @@ class Gutter extends View
           rowValue = (row + 1).toString()
         classes = ['line-number']
         classes.push('fold') if editor.isFoldedAtBufferRow(row)
-        @div class: classes.join(' '), =>
+        @div lineNumber: row, class: classes.join(' '), =>
           rowValuePadding = _.multiplyString(' ', maxDigits - rowValue.length)
           @raw("#{rowValuePadding}#{rowValue}")