add custom request option

[edgji]

I found myself needing to change portions of the AjaxUploader component to get it working with AWS S3. Allowing for the component to have a custom request prop would make extensibility easier.

[coveralls]

Coverage increased (+0.1%) to 31.046% when pulling 7ffa0ca on edgji:custom-request into dbf0735 on react-component:master.

[shepherdwind]

Thanks for you mr, but maybe you should add some document for how to use this option, thanks

[coveralls]

Coverage increased (+0.1%) to 31.046% when pulling 744a778 on edgji:custom-request into dbf0735 on react-component:master.

[edgji]

I added some documentation for the proposed property. Should I add an example to the examples directory?

[shepherdwind]

Thanks very much, example is not necessary.

2.2.0 published