D: Fix li_boost_shared_ptr_runme.2.d compilation.

The overload of Thread.sleep taking a bare integer has been
deprecated/removed.
D: Fix allprotected_not.i compilation.

The director cycle breaking code was emitted when protectors
were not actually enabled on the parent class, leading to
swigIsMethodOverridden being called but not declared.
D: Fix preproc_constants/preproc_constants_c test cases.
D: Fix class/method name ambiguity in test-suite/c_delete.i.

There might be other cases where this happens when $dclassname
is used for code emitted into the proxy class itself, but so
far, there are none in the test suite or any bug reports.
D: Fix name collision between im D module function pointer and actual C function.

Previously, the function pointers were not only declared with
extern(C) calling convention, but actually had C linkage
themselves. Thus, they were exported under their bare names,
potentially colliding with the actual function definitions
in the wrapped library if the dynamic linker decided to
resolve them the wrong way.

This fixes the sneaky1 test case, although I have no idea why
the add() reference in D_add() (via the PLT) is rebound to the
function pointer there and not in all other test cases and
real-world libraries. As far as I can see, there don't seem to
be any special symbol visibility/binding settings involved in
our build system.
Work around D test suite failure due to issue #254.

Object is currently a D keyword for the purposes of SWIG
(that's in fact a little too strict, but Object is the root
of the class hierarchy and some parts of the code break).
'template_typedef_typedef' is supposed to test.
D: Emit empty enums as int aliases instead of omitting them.

This fixes test-suite/enum_forward.i.
D: Use deterministic allocation on the D side in li_boost_shared_ptr_runme.i.
D: Work around nativepointer problem in test-suite/typemap_directorout.i.

Just "%typemap(ddirectorout) MyType &USEME = SWIGTYPE &;" does not
inherit the antivepointer attribute from the SWIGTYPE & case, but
the other typemaps that are not overridden (dout/…). Thus, some
of the emitted code used native pointers, and some SWIGTYPE_p_int.
D: Use configure-detected default language version for test-suite.
D: Fix out-of-source build for examples.
Add D to Travis CI.
D: Fix exception handling support.

The original code was ported from the C# module. It looks like it
tried to avoid reading TLS data by using a shared counter. However,
without also synchronizing on the counter check (or using atomics)
the code is racy. While the races might be benign (the thread that
sets the exception also increments the counter, so when there is
actually an exception, the visible value will always be non-zero
even if it is outdated), they are still undefined behavior,
strictly speaking. Additionally, just using TLS isn't expensive
either.