Motivation:
Now that 4.2 has been released, there's no reason to use the CONVERGENCE
version anymore.
Modifications:
use the RELEASE instead of the CONVERGENCE version of Swift 4.2
Result:
use the latest and greatest
Motivation:
We should support the latest and greatest.
Modifications:
- add Ubuntu 18.04 support (packages exist for Swift 4.2 only)
- add Swift 4.2 support (for Ubuntu 14.04, 16.04 and 18.04)
Result:
- supporting the latest stuff