mp_bits_per_limb with GMP 2.0

OptionMenu is modified.  Somewhat rewritten and elaborated by myself.

class _setit: The constructor now takes an optional argument
`callback' and stashes this in a private variable.  If set, the
__call__() method will invoke this callback after the variable's value
has changed.  It will pass the callback the value, followed by any
args passed to __call__().

class OptionMenu: The constructor now takes keyword arguments, the
only one that's legally recognized is `command', which can be set to a
callback.  This callback is invoked when the OptionMenu value is set.
Any other keyword argument throws a TclError.

Solaris 2 has stub implementations of the POSIX thread functions such as
pthread_detach in libc. This means that configure tries to use them without
-lpthread, then the test of pthread_create fails and the configuration
falls back to the Solaris thread library. This patch moves the test for
pthread_create in -lpthread ahead of the test for pthread_detach in libc.
The patch also ensures that -lpthread is at the start of the library list
when linking, to pick up POSIX thread semantics for fork (see below).

Justification.
Use of POSIX threads on Solaris ensures that the fork() call only runs the
thread that called fork() in the child. This is desirable to prevent (for
example) parent server or database threads running in the child. Sun's
-lthread library uses a traditional fork() which replicates all the
parent's threads in the child. I find this undesirable.

Digression.
The configure.in seems to always test for -lthread even if a POSIX library
is found. I'm not enough of a configure.in wizard to decide whether this is
desirable or how to fix it. It is also irrelevant to this patch - I just
spotted it while testing.
End of Digression.

Only the main thread should survive in the child after a fork().

just a typo in some Linux header; the real symbol is
_SC_AIO_LISTIO_MAX.

comment.  <gerrit@nl.linux.org>

format strings.

This patch allows building the Python 'mpzmodule' under SuSE Linux
without having to install the source package of the GMP-libary.
The gmp-mparam.h seems to be an internal header file.  The patch
shouldn't hurt any other platforms.

diagnostics.

*** INCOMPATIBLE CHANGE: This changes append(), remove(), index(), and
*** count() to require exactly one argument -- previously, multiple
*** arguments were silently assumed to be a tuple.

Added docstrings to tkSimpleDialog.py

This fixes PR#211.

	A change in my last patch could, under certain circumstances,
	cause a loop if the connection to the server dropped while
	waiting for a command completion. I've changed the code to
	re-raise the error after possible debugging output.

    slicing) using long integers

    and _DelItem().
In sequence multiplication by a long, only call PyErr_Occurred() when the
    value returned is -1.

                 Andreas Jung <ajung@sz-sb.de>.

consistency changes and a note that the API may change in the future.

standard library.  Added some comments:

# XXX Note: this is now a standard library module.
# XXX The API needs to undergo changes however; the current code is too
# XXX script-like.  This will be addressed later.

of the current module.  It also runs the tabnanny to catch any
inconsistent tabs.

Also did a little bit of refactoring: added an errorbox() method to
simplify the display of error dialogs.

PyEval_EvalCode() is *not* a "backward compatible interface", it's the
one to use!

enough, it could be negative.  Add i > 0 test.  (Not i >= 0; zero isn't
a valid error number.)

Added FreeMem, MaxBlock and CompactMem calls. The values returned by these are lower bounds in the Python case (as malloc doesn't return memory to the heap) but they can be used to decide when to give low-memory warnings.

	The same problem (mixed mallocs) exists for the pcre stack.
	The buffers md->... are allocated via PyMem_RESIZE in grow_stack(),
	while in free_stack() they are released with free() instead of
	PyMem_DEL().

	The buffers self->regex and self->regex_extra are allocated in
	pcre_compile() and pcre_study() via pcre_malloc, but are released
	via free() instead of pcre_free.

  add clsFilesystemImporter class attribute, alter handling of suffix list
convert suffix importers to funcs rather than instances
remove backwards compat code: Importer.install and 2-tuple get_code()
  result values

switch to isinstance() rather than direct type comparisons
removing chaining concept
update ImportManager.install() to take an optional namespace to install
  itself in. this will be useful for setting up rexec environments.
minor comment nits