Gwenhywfar

Revert "MsgEngine: Further improved readabilty."

This reverts commit 3ae5e69990845c6edf69502b3d661ac6903b639c.

Revert "MsgEngine: More work on improving maintainability."

This reverts commit 6c2f9046916ed0efcc6b40c07e6bd2b916959769.

Revert "MsgEngine: Started refactoring of msgengine."

This reverts commit 7db0eea44f5ce73bbb2a1832cb855713cafba610.

Fix compiler error with mingw-x86_64: "long int" is still 32bit there.

Hence, the 32 bit "long int" must be cast to a 64bit int first, then
to a pointer. Explained here nicely:
https://stackoverflow.com/questions/384502/what-is-the-bit-size-of-long-on-64-bit-windows?noredirect=1&lq=1...

Fix detection of <libintl.h> for windows cross-compile environment.

It is not available in a plain Ubuntu 18.04 mingw-w64 cross-compile
package, so configure must correctly detect that it is not there.
It is available in the gnucash jhbuild env, though. This should...

Provide visibility to Qt5 dialog code

Make the Qt5 dialog code available so that it can be sub-classed.

Simplify gnutls lookup: pkg-config is fine for windows, too.

Also, as gnutls>=2.9.8 is required, the check for the function
that exists since >=1.6 is no longer needed.

MsgEngine: Started refactoring of msgengine.

BUILD: Include -Wunused-parameter.

MsgEngine: More work on improving maintainability.

MsgEngine: Further improved readabilty.

MsgEngine: Started improving readability.

- split msgengine.c into multiple files
- split spaghetti code functions into smaller parts

Update German translation

Result of "make merge".

SAR: Disabled warnings.

Result of "make format".

Fixed typemaker2 targets.

Having these targets sometimes leads to "make" thinking that files have
to be rebuilt by typemaker2.

Prepared release 4.99.24rc8.

Improve makefiles: If astyle is not there, just replace it with no-op echo because compiling is nevertheless possible.

Add gnutls include flags explicitly in those Makefiles where they are needed.

Windows: Fix missing GWENHYWFAR_CB declaration of testSignals function.

Fix compiler warning about unused variable if HAVE_I18N is unset.

Fix printf format specifiers for windows compatibility using macros from <inttypes.h>

Now really fixed after d86a71a0 and deccd267.

Fix another windows printf format specifier.

Similar to and copied from be69cdb9.

Fix missing GWENHYWFAR_CB attribute at function definition.

Was missing since aee95892, checked with cross-compile to i686-w64-ming32 host.