Workflow: `drought` -> `agws`

Identify events and calculate recession coefficients from a time series
-  `agws`: `run_model drought drought 02040000 auto agws`
   - `download`: `run_model drought drought 02040000 auto agws download`
   - `analyze`: `run_model drought drought 02040000 auto agws analyze`

#### Example
```
cd /opt/model/p6/vadeq
. hspf_config
run_model drought drought 02040000 auto agws

```