We need to make a few more modifications here to have it be cross platform.

* In Linux, it doesn't seem that sp.call accepts a single string with all the arguments, and expects an array like:
`sp.call(["ipython", "notebook", dstloc]`
* It's not safe to assume where the `ipython` executable is located. I think it'd be better to just assume the user needs to add it to their path and just call `ipython`.
* Since the `CREATE_NEW_CONSOLE` flag isn't available on Linux, we need to try some other way to start IPython without blocking the process (you probably saw that currently without this flag, flask will be blocked and the `render_template` never happens). Check out [`subprocess.Popen`](https://docs.python.org/2/library/subprocess.html#subprocess.Popen). We might need to check stdout or stderr to make sure ipython starts safely.