import from cli

addresses #390

This update allows you to run something like:
`./st --port=7080 /home/ubuntu/test.json`
from the terminal. 

The pattern is imported and automatically started once ST starts. 

You can have multiple arguments for importing multiple patterns into the same st at launch.

`./st --port=7080 /home/ubuntu/test_1.json /home/ubuntu/test_2.json`

No flag necessary.