Merge branch 'maint' into branch-1.11, msvc and master
* maint:
tests: avoid a spurious failure of 'ltinit.test' MinGW
tests: testsuite is now safe to run with dmake in parallel mode
tests: fix spurious failures w.r.t. parallel make and colorization
tests: fix spurious failure in 'distcheck-override-infodir.test'
tests: avoid another failure of 'uninstall-fail.test' on Solaris