Issue #139: Using the library as a module (i.e. "var pdfMake = require('pdfmake')")

#139: Removing Grunt task "concat" since this destroys the possibility to use pdfmake.js as a module.
Instead added the fileSaver.js (saveAs) as a require to pdfMake.js. This works for me as a module now and also still as a <script> include.
I also increased the version, just in case you wanna release this right away.
Resolves the issue https://github.com/bpampuch/pdfmake/issues/139.