[CREATE] perl binding of the FontVal FreeType backend

[Hin-Tak Leung]

Hi.

It was over a year ago when I took some initial interests with perl binding of FreeType and hoping to see a perl-based work flow on analyzing hinting instructions in fonts.

It has finally happened. It is currently sitting in my hard drive and at some point will land in possibly the "font-diag" branch with an example script at
  https://github.com/HinTak/p5-Font-FreeType
(just like the "font-diag" branch of my freetype-py python binding which contains FontVal specific code).

Some of the non-FontValidator-related changes are being pushed upstream to p5-Font-FreeType. People who are interested in perl binding of FreeType are welcomed to have a look at the pulls, etc. After the generic changes / additions land upstream, I'll create the font-diag branch on my perl FreeType binding fork.

Some FontVal-specific changes are in my SharpFont (C# ) fork.

While looking at the perl binding of FreeType, I thought I might need to change how the FontVal FreeType backend talks to a frontend (currently C#, python, perl) again to make it easier for a perl-based client. But hopefully this is the last time.

(strictly speaking, the C<->non-C interface has only changed once since MS Font Validator got open-sourced - the 2nd change happened a few months ago and hadn't made it into a release yet)