README: add venv instructions

[proppy]

/cc @Fleker @devunwired can you test on a Mac?

Closes #41

[Fleker]

pip install google-auth-oauthlib[tool] --user Ran the first command on Mac. Seemed like the tool downloaded.

Then tried to run the command: -bash: google-oauthlib-tool: command not found

[irataxy]

I got the same results as @Fleker.

[proppy]

@irataxy @Fleker can you check if this got installed in ~/Library/Python/2.7/bin it might be missing in your $PATH.

[irataxy]

It was installed in that location:

ls -l ~/Library/Python/2.7/bin total 72 -rwxr-xr-x 1 nickcook eng 236 Jul 25 08:40 google-oauthlib-tool

[proppy]

@irataxy can you check if PYTHONUSERBASE is defined:

echo $PYTHONUSERBASE

[proppy]

And please also try:

python -c 'import site; print(site.USER_BASE);

[irataxy]

nickcook-macbookair:~ nickcook$ echo $PYTHONUSERBASE

nickcook-macbookair:~ nickcook$ python -c 'import site; print(site.USER_BASE);

print(site.USER_BASE);

[irataxy]

python -c 'import site; print(site.USER_BASE); did not print anything out

[proppy]

Then maybe it's best to document how to create the virtualenv.

[proppy]

@irataxy @Fleker PTAL

[proppy]

@Fleker should we merge this?

[Fleker]

It will be useful to include these instructions in the README.

[proppy]

Taking that as a LGTM :)