Revert "Fix travis command line."

This reverts commit 47b742e7932b4a80d369e1c490d240eb77cbccba.
Revert "Install newer boost version for travis checks."

This reverts commit c9e4e35ecd1513ba2a28434a5ac03176a8041089.
Fix failing test case on older systems.

std::minmax returns references and this makes problems in this case.