Add FAQ to address potential vs-emr install issues for VS on AWS EMR

[lynnlangit]

FAQ for OSX users
Q: Do I need to download the entire source from GitHub to install VS on AWS EMR?
A: No, but it's the simplest way to get the files you need for the install

Q: If I get some kind of permissions error when I attempt to install vs-emr what should I do?
A: Install using sudo -H pip install --user ./python

Q: If I attempt to use vs-emr and I get the command not found error what should I do?
A: Run sudo find / -name "vs-emr" to find the install path and then run vs-emrusing the full path, for example sudo /private/var/root/.local/bin/vs-emr

Q: If I attempt to create an EMR cluster and it fails, read the error message.
A1: If error is default config not found, then mkdir ~/.vs_emr, copy config.yaml into that new directory cp conf/config.min.yaml ~/.vs_emr/config.yaml, then edit config.yaml to replace values as required (do NOT use quotes around values)
A2: If error is unknown options: --<some parameter>,<some value>, etc..., verify your version of the awscli client tool aws --version, minimum supported version is aws-cli 1.10.22. To upgrade awscli run sudo -H pip install awscli --upgrade --user
TIP: you can attempt to run the generated awscli code directly in your terminal (i.e. without vs-emr) to get more detailed error messages. An example is at the end of this note. You can remove EMR options as needed, depending on your version of awscli.

Q: How do I know that the vs-emr command succeeded in creating a cluster?
A. You will see a "ClusterId" value (as shown below). TIP: Remember to immediately submit your analysis job as the cluster is set to auto-terminate.