#115: add ajax_loader.js
#115: add loading.gif
#115: form_svm.css, define style for '.ajax_loader'
#115: tests/php/index.php, add reference to 'ajax_loader.js'
#115: html_form_ajax.js, remove 'this' 'ajaxLoader()' param
#115: ajax_loader.js, remove options / class override
#115: html_form_ajax.js, call ajax_loader.js
#115: html_form_ajax.js, implement ajax overlay
Merge pull request #118 from jeff1evesque/js_ajax_loader

#115: Implement ajax overlay graphic