Convert the base64 encoded data to a Blob to allow for exports of larger tables

[ghost]

The problem

The current implementation encodes the tables in base64 and creates a download href. But this approach has a limit on how large can the base64 data be for the browser to be able to download/create the file.

Where it failed

I had trouble exporting >10000 rows with 2 columns only

The solution

A Blob object is created from the base64 encoded data, and a the anchor href is just a reference to that blob object. The explanation is taken from a stack overflow comment

[craignicol]

I had a similar solution in #44 but this looks slightly more robust.

[craignicol]

How about adding the msSaveBlob to add IE support, now you've got the heavy lifting to use blobs

[ghost]

Thanks for the comment, I just saw your code, I'll try to combine it with these changes, but i'll have to set up my windows env first 😄 i'm running linux currently

[craignicol]

Just tested it myself, works on Chrome, IE and Edge, but not Firefox gives me TypeError: Argument 2 of URL.createObjectURL can't be converted to a dictionary. at excellentexport.js:178:27

I used { type: 'application/vnd.ms-excel'} as the type to support both Chrome and Firefox (and an equivalent dictionary for csv)

[craignicol]

Firefox requires the export type to be of the format "{type: exporttype}"

[jmaister]

Merged the pull request. Thanks @atanasovskib !!

It had some conflicts but works great.

[gspringtech]

The Firefox error persists in the 2.0.0 version (downloaded today) for Firefox 49.0.1 when using the CSV export.
A temporary fix involves replacing "exporttype" on line 105 with
{ type : exporttype}