Compat also in submodules, and about libpango

[hustf]

I got this error on 0.4.6. A lot of messages because of redefinition of functions are suppressed.

include(singraph.jl)
....
ERROR: LoadError: UndefVarError: Compat not defined
 in pango_parse_markup at C:\Users\F\Documents\GitHub\GLVisualize.jl\src\compose_backend.jl:451```

I added Compat at the start of this file, but ran into another issue from the same line:

ret = ccall((:pango_parse_markup, Compose.libpango), ....

Compose only exposes libpango after checking for Compose.insinstalled("FontConfig"). You could do the same, but this would not fix this dependency. It would just crash more elegantly. And this silent dependency adds another thing that the user has to figure out is necessary after trying other stuff first.

Fontconfig is not being mainained very actively. It's just a tiny wrapper around libpango, and it currently does not precompile. What's your thoughts here? I don't know why FontConfig doesn't precompile.

[hustf]

Not the most elegant solution here, but it works locally.

FontConfig doesn't know about the alias libfontconfig-1.dll for libfontconfig. libfontconfig.dll is not longer available, it seems.

I copied libfontconfig-1.dll, renaming the copy libfontconfig.dll, into C:\Users\F.julia\v0.4\WinRPM\deps\usr\x86_64-w64-mingw32\sys-root\mingw\bin\libfontconfig-1.dll

and voila, the compose examples work and Gadfly plots looks better, supposedly.

[SimonDanisch]

Thanks! I'm not really sure what the current state of Compose is right now. When I tried to make things work I got weird syntax errors! I will keep an eye on it.

[SimonDanisch]

I opened #122 to track the backend failure. I'm not really sure what to do about Fontconfig. Maybe I'll just start using the font fallback permanently ;)