Implement xlocale APIs from Darwin, mainly for use by libc++. This adds a
load of _l suffixed versions of various standard library functions that use
the global locale, making them take an explicit locale parameter. Also
adds support for per-thread locales. This work was funded by the FreeBSD
Foundation.

Please test any code you have that uses the C standard locale functions!

Reviewed by: das (gdtoa changes)
Approved by: dim (mentor)

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

MFC r196916:
Fix a list overrun.

Sponsored by: Sandvine Incorporated
Approved by: re (kib)

Import a vendor fix for a list overrun.
This has been considered as a security hole on some specialized ml,
but currently the secteam@ doesn't consider that way.

Reviewed by: emaste, des
Sponsored by: Sandvine Incorporated
MFC after: 3 days

- Import the HEAD csup code which is the basis for the cvsmode work.

On platforms where long is 64 bits, make sure gdtoa doesn't use a
long when it really wants an int.

Merge local diffs.

Import of the latest gdtoa sources, which include fixes for minor
problems relating to NaNs and rounding.

Configure gdtoa so that floating-point numbers are correctly rounded
when they are printed in non-default rounding modes.

Userland spinlocks bad. Sleep locks good.
Use the latter for gdtoa.

Requested by: deischen (far too long ago)

Add some missing prototypes to eliminate some warnings. These already
appear without leading underscores in gdtoa.h, but this approach avoids
removing that file from the vendor branch and unduly rearranging things.

Prodded by: nectar

Add missing prototype for gdtoa().

Enable locale support in strtod() and dtoa().

Noticed by: ache
Reviewed by: mike (mentor)

Local patches:
- include extra system headers and add appropriate #defines
- use a spinlock to synchronize parts of gdtoa
- protect exported symbols with leading underscores

Reviewed by: bde (briefly), mike (mentor), obrien

Initial import of David Gay's gdtoa library for conversion between
strings and floating point.