Set system variables for the Cobol compiler

Set $COBDIR to the location where the Cobol compiler is installed.
Ensure that $COBDIR/bin is defined in your system PATH.
Ensure that $COBDIR/lib is in your shared library path.
Add the following variable definitions to the environment variable management script.
```
$COBDIR
$COBLIB=$COBDIR/lib
PATH=$COBDIR:$PATH 
```