libdecnumber: Fix decDebug64 extension
libdfp: Enable BID for 32bits

This patch adds BID support for 32 bits. BID current relies on 128-bit
type support, which is supplied by GCC/clang extension __uint128_t.
Some architectures, however, does not support this extension
(x86 32 bits, for instance).

In these case the mini-gmp implementation from libgmp is used to supply
a multiprecision math library (set to emulate a 128-bit int type).
Currently it is included direct in libdecnumber/decimal128.c object and
thus used in other parts of libdfp through libdecnumber.a static
library.
libdfp: Clean configure.ac from GLIBC support

This patch cleans the remaning GLIBC build support from configure.ac.
It also setups the minimum autoconf to 2.63 (RHEL6/CENTOS6).
libdfp: Fix __SIZEOF_INT128__ dependency

Some GCC version do support __uint128_t, however they do not define
__SIZEOF_INT128__.  This patch adds a configure support to check if
the compiler actually check for 128-bits supports and sets
HAVE_UINT128_T define.
Merge branch 'master' of github.com:libdfp/libdfp into rzinsly-master
libdecnumber: Fix warning due braced-groups within expressions

The libdecnumber uses the -pedantic compiler options that triggers
the compiler warning when braced-groups within expressions is used.
This patch removes its utilization within libdecnumber code.
libdfp: Disable C++ tests if compiler does not support it

This patch disable the C++ tests if the compiler does not have support
for std::decimal header/types.
Merge branch 'master' of github.com:libdfp/libdfp into rzinsly-master
libdfp: Added definitions for the number of digits in strings.

This patch defines the lenght of strings with the digits of a _Decimal, and use
this on the code. This fixes a bug in numdigits function.