Support for older browsers

[altkatz]

tested on IE 8

[coveralls]

Coverage remained the same when pulling a27c77a on altkatz:master into 0099463 on SheetJS:master.

[SheetJSDev]

@altkatz thanks for pointing this out! It saddens me to see that jshint doesn't pick up on trailing commas

The gh-pages branch has a shim for IE8 and below which includes what is necessary. That probably should be included in master.

Can you make a few small changes:

1. remove the trailing comma in the file bits/34_extprops.js -- https://github.com/SheetJS/js-xlsx/blob/master/bits/34_extprops.js#L14

2. add the file shim.js (from the gh-pages branch) into the master branch (and update the README note to reflect that the shim.js is there)

3. squash down to one commit.

I will make some more improvements in the next commit that will help prevent this. (I've been playing with https://www.npmjs.org/package/jscs locally and there are configuration options for detecting trailing commas)

[altkatz]

@SheetJSDev shim.js added to master.

[coveralls]

Coverage remained the same when pulling 71dd522 on altkatz:master into 0099463 on SheetJS:master.

[SheetJSDev]

@altkatz thanks for making the changes. If possible, can you squash the three commits down to one ?

[SheetJSDev]

@altkatz I went ahead and squashed it. Even though the PR won't show as merged, the commit credits you a96b723

[SheetJSDev]

Version 0.7.6 includes the referenced changes