Merge branch 'bionic' of https://github.com/evverx/util-linux

* 'bionic' of https://github.com/evverx/util-linux:
  travis: make it easier to switch to the next clang/gcc
  travis: switch to clang-10
  travis: switch to gcc-10
  travis: ignore memory leaks in checkusage
  travis: install all the "official" build dependencies
  travis: switch to Bionic