Travis: Perform installation test on 32-bit build.
Travis: Add flag to force building of dependencies.
Travis: Change search pattern for core dumps.

Would otherwise find files in .deps if dependencies are built.
Travis: Simplify clint script.
Travis: Remove setting core file size.

Doesn't work on Travis:

> bash: line 0: ulimit: core file size: cannot modify limit: Operation not permitted
Merge pull request #1570 from fwalch/travis-improvements

Travis-related improvements