Moved inotify_rm_watch out of the generic notbsd target and into specific linux and android targets because the second argument has a different type in android and linux.

Broader sendmmsg() / recvmmsg() support

As a prerequisite for getting `sendmmsg()` / `recvmmsg()` into nix ( https://github.com/nix-rust/nix/pull/1017 ), support for non-linux platforms needs to be added in libc.

The initial commits in this PR will just be to test out target support via CI.

Add IP_ORIGDSTADDR and others on FreeBSD.

A follow-up from #1252.

CC @asomers.

r? @gnzlbg

Add missing group entry functions for Solaris/Illumos

This commit adds definitions for `setgrent`, `endgrent`, and `getgrent` which were missing (but available for FreeBSD and other *nix systems).

Allow installing rustfmt component to fail

This commit adds definitions for setgrent, endgrent, and getgrent
which were missing (but available for FreeBSD and other *nix systems).

Re-enable debug output in dox.sh and remove unused variable in runtest

Always use the latest ctest

A follow-up from #1252.

CC @asomers.

r? @gnzlbg.

Temporarily allow Android build jobs to fail

These are still too brittle for some reason.

Clean up documentation generation

Add IP[V6]_[RECV]ORIGDSTADDR for Linux and Android

Add support for illumos target

This change adds support for an illumos os target to libc.  Similar to the BSDs, there is a large deal of overlap (given the common history), so the 'solaris' directory was renamed to 'solarish' (it's the closest thing to an official term to refer to things descending from Solaris as well as Solaris).  There were also a number of missing definitions (as well as a couple missing functions) that have proved necessary for building a number of rust programs on illumos or Solaris.

Portions contributed by @papertigers .

Do not allow rustup to fail

Currently if rustup fails to download something the build will continue until that something is needed. This makes the job fail early and clearly.

and Solaris-derived distributions (i.e. illumos).  In addition, a number
of missing definitions (and compatability functions) that have been
found necessary to run a number of rust binaries on illumos have been
added.

Portions were contributed by Mike Zeller <mike@mikezeller.net>

unbreak openbsd after #1217

Fix license badge