[show-hint addon] Fix bug where hint at start of line didn't close on backspace

If cursor started at the beginning of a line and show hint was
triggered, adding then deleting a character would not close the hint
correctly.

Author: 40thieves

addon/hint/show-hint.js

@@ -98,7 +98,7 @@
       var pos = this.cm.getCursor(), line = this.cm.getLine(pos.line);
       if (pos.line != this.startPos.line || line.length - pos.ch != this.startLen - this.startPos.ch ||
           pos.ch < this.startPos.ch || this.cm.somethingSelected() ||
-          (pos.ch && this.options.closeCharacters.test(line.charAt(pos.ch - 1)))) {
+          (!pos.ch || this.options.closeCharacters.test(line.charAt(pos.ch - 1)))) {
         this.close();
       } else {
         var self = this;