Course Status Tracker - Fix for Language and Notice: Trying to get prope...

...rty of non-object

This patch addresses the following issue:

* Applies Moodle output filtering to data coming from database so that
  it gets formatted correctly if using the Multi-lingual or Multi-language
  plugins.
* Applies date formatting using the userdate() function so that dates
  now appear in the user interface language.
* Fixes the following notice which appears in the Course Enrolment Report
  (viewpage 2):
  Notice: Trying to get property of non-object in /www/phacmoodle/moodle/phac-moodle/blocks/course_status_tracker/lib.php on line 145
* Fixes the following notice which appear in all viewpages except 1 and 2:
  Notice: Undefined variable: a in /www/phacmoodle/moodle/phac-moodle/blocks/course_status_tracker/view.php on line 75
* Removed CENTER tags that were formatting the header table. CENTER is not
  supported in HTML5 standard (was deprecated before that already)
  (WCAG 2.0)
* Removed TABLE and related tags that were formatting the H2 header.
  Tables should not be used for the purpose of formatting content on a
  page. This also allows themes to apply their own colour schemes using
  styles for a more consistent overall site presentation (WCAG 2.0).
* Fixed some minor typos.
* Fixed some source code formatting issues such as:
  - inconsistent indentations
  - tabs instead of space
  - trailing spaces
* Include the changes published on moodle.org in version 2013060701 and
  2013060702 (current version on GitHub - 2013060700 - is outdated)

Please contact me if you have any questions or concerns regading these
modifications.

Signed-off-by: Michael Milette <michael.milette@instruxmedia.com>