Nullpointer Exception table with filter and no data

[mambarek]

user the plugin for

• an empty HTML-Table (no rows)
• the options data attribute is not defined
• define filters for some cols

this throws a Nulllpointer exception in line 899 initializing filter.
to fix this I add a acondition in the line 165 as follow

if(this.data)
this.filter();

Backround: my table is a table to manage employees. So at first time i don't have any employee. click a button to create an employee, after saving i become data.

so more tests for an empty table throws more exception because the filter and sort are too data based. so to avoid this i put all this in the same condition

if (this.data) {

    /* Add sorting class to all th and add callback. */
    this.createSort();

    /* Add filter where it's needed. */
    this.createFilter();

    this.triggerSort();

    this.filter();
}