Added ability to trigger sort programmatically

-Added event on table level to trigger sort on a specified column in
specified direction (optional)
ex: $('table').trigger("sorttable", {column: 3, direction: "desc"});
-Started from brazenbits version which implemented "ability to specify
default sort"
(https://raw.github.com/brazenbits/Stupid-Table-Plugin/3a71672862dadee4657372723964cbab1ca3d9ad/stupidtable.js)