Use local example scripts for the online playground

[ramnathv]

For some reason, the gist API has trouble working on IE (CORS issues). Moreover API limits mean that the same IP address cannot generate more than 30 requests per hour. Given this, it might make more sense for me to move the example scripts to the playground folder.

The easiest way to do this seems to be to download the json from the API request to the gist and fetch it instead. Longer run, I can simply write a script that will take a list of R files and generate the json payload.

[ramnathv]

It would be good if the playground can be flexible enough to load an example from a gist or a collection of examples from a gist. This would allow sharing of persistent links.

[ramnathv]

Move ace editor files to repository for faster access. Right now, the syntax highlighting themes take some time to load.