Header goes out of table frame

[maciejkaiser]

Hi,

I have a problem with this plugin. When in table are many columns, and user scroll these data to left side - header is going beyond the frame. Table structure is similar to scrollable-div.html in demo folder. I have a div contains another div with table, no styles but overflow:auto and height:600px;

[amadeuszi]

My pull request #149 fixes the issue