- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Export gdtoa's __ULto{x,Q}_D2A routine in a private namespace so
libm can use it.

Remove symbols that should not be exported.

Submitted by: das
MFC after re@ approval

Use C comments since we now preprocess these files with CPP.

Don't export __gdtoa. The only known ports that rely on
this or the deprecated POSIX functions {e,g,f}cvt() have
newer versions that do not (rely on them).

Requested by: marius

Add __gdtoa to the list of FreeBSD private symbols. Unfortunately,
this is used by some 3rd party applications when {e,f,g}cvt() are
not found. POSIX defines the xcvt() funtions but says they are
deprecated in favor or sprintf(). We'll import these functions
from OpenBSD and remove __gdtoa() from the exported interfaces
when libc version is bumped.

Add symbol maps and initial symbol version definitions to libc.

Reviewed by: davidxu