Patch to allow batch merge

[rcsteins]

Hey,

I made a patch to allow the Client class to perform batch merge calls( the current code only supports single merge requests as far as I can tell.

Its probably not in the style you want currently, so do you mind if I send a pull request and you can let me know how I should restructure it to be acceptable. Also I probably need to write a test.

[jheth]

Yes. Please send over any pull request you want.

[gnilrets]

I would like this too.

[jheth]

@rcsteins I know it's been a while, do you mind opening a PR for batch merge support? I'd like to see it.

[rcsteins]

Sent it. Did my best to fit it into the current code style.

Let me know if you have any questions

[rcsteins]

I also needed batch convert lead so that's included as well.