[DONE] Configure runtime test for decimal floating point support in compiler.

[DONE] Configure test for glibc 2.10 headers.

[DONE] Configure runtime test for glibc 2.10 based on register_printf_type()
function..

Add --with-cross feature to prevent the make check suite from being executed
on the build machine.

Add --export-test feature to export the test-suite into stand-alone static
test cases.

libdecnumber.so phantom library for compat issues.

libdfp version issues with older apps.

[DONE] If system glibc is 2.10 then make check shouldn't need all the GLIBC build
scaffolding for executing and debugging tests.

Clear up make clean and make distclean.

Clear up dependency issue so that libdfp.so.1 is rebuilt when a .c file
changes.

Finish make check test suite.

Clear up symbols and hidden symbol usage and export and make sure we aren't
using the PLT from within libdfp.

Optimize the math routines for hardware dfp support.

Implement dpd backend for x86 and x86_64.

Prototype versioned symbols support.

Implement libbid backend for x86_64.

[DONE] Write User's guide

Write Man Page

Write User's guide in docbook format, .i.e. info file.
