- Copy 17 functions definitions from src/unix/mod.rs
      to src/unix/bsd/mod.rs src/unix/haiku/mod.rs
      src/unix/notbsd/linux/mod.rs and src/unix/solaris/mod.rs
    - Add some functions to android that was cfged out
    - Remove cf* and tc* functions implementations for android
      (they are available with api >= 12, which was release in 2011)

Add ppoll() for all unix platforms

I'm unsure of whether there is support in OS X for this, and I can't find anything online (so I'm betting there isn't), but I'm going to let this run through CI to confirm.

Added baudrate constants.

Addresses #528, adding baudrate constants for `bsd` and `notbsd` flavors of `unix`.

Passes `libc-test` locally on ubuntu 14.04 LTS with the additional (uncommitted) entries into in `build.rs`:

```
cfg.skip_const( move |name| {
        match name {
            # ... snip ...
            "PTRACE_O_SUSPEND_SECCOMP" |
            "CLONE_NEWCGROUP" |
            "NETLINK_LIST_MEMBERSHIPS" |
            "NETLINK_LISTEN_ALL_NSID" |
            "NETLINK_CAP_ACK" |
            "PR_CAP_AMBIENT_CLEAR_ALL" |
            "PR_CAP_AMBIENT_LOWER" |
            "PR_CAP_AMBIENT_RAISE" |
            "PR_CAP_AMBIENT_IS_SET" |
            "PR_CAP_AMBIENT" |
            "PR_FP_MODE_FRE" |
            "PR_FP_MODE_FR" |
            "PR_GET_FP_MODE" |
            "PR_SET_FP_MODE" |
            "PR_MPX_DISABLE_MANAGEMENT" |
            "PR_MPX_ENABLE_MANAGEMENT" |
            "PR_GET_THP_DISABLE" |
            "PR_SET_THP_DISABLE" |
            "PR_SET_MM_MAP_SIZE" |
            "PR_GET_MM_MAP_SIZE" |
            "PR_SET_MM_MAP" |
            "NLM_F_DUMP_FILTERED" |
            "EPOLLEXCLUSIVE" => true,

            _ => false,
        }
    });
```
I'm assuming this is because I'm stuck using `linux-libc-dev:3.13.0-24.46` for the moment and those constants are defined in newer versions.

- some tests are failing
- remove readlink, timegm and sig* functions in favor of the
  unix/mod.rs definitions
- remove time64_t (it is not defined for aarch64)
- move some definitions to android/b32.rs and create appropriated
  definitions in android/b64.rs

```
export TARGET=x86_64-unknown-openbsd
export QEMU=openbsd.qcow2
sh ci/run-docker.sh $TARGET
```
Passes when run localy.

Adding `termios.h` behind `rpcsvc/rex.h` does not solve the #define
clash since `rex.h` also defines the `_SYS_TERMIOS_H_` include guard.

I'm unsure of whether there is support in OS X for this, and I can't find
anything online (I'm betting there isn't), but I'm going to let this run
through CI to confirm

add tmpnam and pthread_exit

tmpnam and readdir are trivial IMO.

About the `pthread_create` change: It needs `unsafe` for passing `C` functions to pthread_create (with rust functions the omission of `unsafe` is working of course).

`bindgen` produces this function definition:

```
pub fn pthread_create(arg1: *mut pthread_t,
                      arg2: *const pthread_attr_t,
                      arg3: Option<unsafe extern "C" fn(arg1: *mut c_void) -> *mut c_void>,
                      arg4: *mut c_void) -> c_int;
```

So it would add an additional `Option` around the function. But that would break existing code which uses `libc::pthread_create` and what use is it to call pthread_create without any function pointer, so I left `Option` out.

For reference: I also opened a [stackoverflow question](http://stackoverflow.com/questions/42284562) where the answers were also suggesting adding `unsafe` to the function definition.

Add definitions to Android to allow fs2 crate compile

This is the only missing part to allow cargo to compile on android.

Make readdir available on all unix targets

The readdir_r call has problems, and we'll probably want to move to
readdir on many, if not most, unix targets. This patch makes readdir
available in unix, rather than just solaris as before.

See https://github.com/rust-lang/rust/issues/40021

Apparently a lot of libc's don't put "const" on the return type for
readdir, which causes type mismatch.

The readdir_r call has problems, and we'll probably want to move to
readdir on many, if not most, unix targets. This patch makes readdir
available in unix, rather than just solaris as before.

See https://github.com/rust-lang/rust/issues/40021

Add jail functions and constants for FreeBSD

These are the system calls for creating and managing jails on FreeBSD.

Having the B* constants in `unix/notbsd/mod.rs` passed CI tests
except for powerpc.  So we'll try moving into individual
arch/ABI that the CI tests cover for now. This commit should
pass for the following:

- mips32
- mips64
- musl32
- musl64
- android32
- android64
- arm32
- aarch64
- x86
- x86_64

Then we can figure out the powerpc variants.  This also prevents
potential errors for sparc64 which is not covered by CI.

Attempting to correct for conflicting defines from `rpcsvc/rex.h`