I generally hear it in the phrase "the whole shebang" and in informal sentences like the one you have quoted. Have a look at: http://fraze.it/n_search.jsp?q=shebang&l=0
September 28, 2016
I think it's also a pun. If you read it as "she" + "bang!" (which would be pronounced differently to "shebang") it conveys the idea of woman + explosion/noise/surprise/etc. So it's quite a clever name!