Merge branch 'unshare_clear_environ' of https://github.com/cgoesche/util-linux-fork

* 'unshare_clear_environ' of https://github.com/cgoesche/util-linux-fork:
  nsenter: use clearenv() only when it is available
  tests: (unshare) add --clear-env option tests
  tests: (test_strerror.c) use ARRAY_SIZE for better readability/portability
  tests: (test_strerror.c) add EPERM errno support
  bash-completion: (unshare) add --clear-env option
  unshare: (manpage) fix minor typos
  unshare: new option to prevent environment variable inheritance

# Conflicts:
#	tests/helpers/test_strerror.c

diff --cc sys-utils/nsenter.c
Simple merge

diff --cc sys-utils/unshare.c
Simple merge

diff --cc tests/helpers/test_strerror.c
index 322ce659bef9bfd9d293f52d1f1f7d7cb941bfaf,3775a46a33fc90676a3ce31b200713fd47019ff6..e0ad21e6d60e2b51119927f053d9e90fc646fe84
--- 1/tests/helpers/test_strerror.c
--- 2/tests/helpers/test_strerror.c
+++ b/tests/helpers/test_strerror.c
@@@ -21,7 -24,7 +24,8 @@@ static struct 
        E(ENOTTY),
        E(EILSEQ),
        E(EINVAL),
 +      E(ERANGE),
+       E(EPERM),
  };
  
  int main(int argc, const char *argv[])