* added plugin 'qtip2' to provide 'tooltips';
  employed in adding/modifying record data to provide validation info;
* added 'ajax_modify_record' url; removed 'ajax_edit_history_data' url;
* added 'indicator.views.ajax_modify_record()' for 'EditHistoryData.html';
* renamed 'indicator.views.add_recordhistory()' to 'add_recordhistory_view()';
* added 'indicator.tools.add_recordhistory()';
* added 'pytz' to 'env/requirements.pip';
  'pytz' to handle timezone in python & django (recommended)