Re: [RFC] building postgres with meson -v8

Here is a patch that adds in NLS.

There are some opportunities to improve this.  For example, we could 
move the list of languages from the meson.build files into separate 
LINGUAS files, which could be shared with the makefile-based build 
system.  I need to research this a bit more.

Also, this only covers the build and install phases of the NLS process. 
The xgettext and msgmerge aspects I haven't touched at all.  There is 
more to research there as well.

The annoying thing is that the i18n module doesn't appear to have a way 
to communicate with feature options or dependencies, so there isn't a 
way to tell it to only do its things when some option is enabled, or 
conversely to check whether the module found the things it needs and to 
enable or disable an option based on that.  So right now for example if 
you explicitly disable the 'nls' option, the binaries are built without 
NLS but the .mo files are still built and installed.

In any case, this works for the main use cases and gets us a step 
forward, so it's worth considering.