Allow completion to specify that the suffix should be removed, fixes #5.

For a completion like
{
  name: "dictionary",
  replaceText: "dictionary",
  deleteSuffix: true,
  meta: "Dictionary",
  priority: 100
}
taking that suggestion for digtio^nary will actually replace the
whole word.

package.json

@@ -11,7 +11,6 @@
     },
     "dependencies": {
         "acorn": ">=0.11.0",
-        "amd-loader": "",
         "async": "^0.9.0",
         "base64id": "~0.1.0",
         "c9": "",
@@ -49,7 +48,7 @@
     },
     "licenses": [],
     "c9plugins": {
-        "c9.ide.language": "#77f75c7635",
+        "c9.ide.language": "#64aeeed087",
         "c9.ide.language.css": "#ef8a28943e",
         "c9.ide.language.generic": "#32986699ac",
         "c9.ide.language.html": "#bbe81afed1",