`xml.h` required `stdio.h` to be included first, which is unfortunate. Switch `xml.c` include order to include `xml.h` first in order to catch such mistakes in the future.
Now using modern CMake features as discussed by Daniel Pfeifer on C++Now 2017. Moreover a full build environment is defined by the provided [mini-cross](https://github.com/ooxi/mini-cross) description.
Squashed commit of the following:
commit 3501a6d4a4
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:10:37 2012 +0100
Open XML document...
commit e4f6335425
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:10:04 2012 +0100
Open XML document...
commit cf9b46c260
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:09:56 2012 +0100
Open XML document...
commit be3baa3d99
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:09:48 2012 +0100
Open XML document...
commit 9be46ba2cf
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:07:35 2012 +0100
Open XML document...
commit 081a599747
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:06:58 2012 +0100
Open XML document...
commit 4af3334803
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:05:24 2012 +0100
Open XML document...
commit f5c3a25541
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:04:30 2012 +0100
Open XML document...
commit 81ee66c39e
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:02:53 2012 +0100
Open XML document...
commit 1448aa1484
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:02:03 2012 +0100
Open XML document...
commit dc767c8d67
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:01:14 2012 +0100
Open XML document...
commit ad23dcc127
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 16:00:25 2012 +0100
Open XML document...
commit f7c905130d
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:59:31 2012 +0100
Open XML document...
commit 1cce95d462
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:57:29 2012 +0100
Open XML document...
commit 1b3fa5f684
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:45:03 2012 +0100
Open XML document...
commit 0778105ea2
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:41:48 2012 +0100
Open XML document...
commit 64418dcb81
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:41:06 2012 +0100
Open XML document...
commit 54061a0e3b
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:40:39 2012 +0100
Open XML document...
commit e776734fa2
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:39:39 2012 +0100
Open XML document...
commit 81bbf1e0c3
Author: ooxi <85fcd0ef4ec8@f977375cdcd6.anonbox.net>
Date: Thu Nov 1 15:38:36 2012 +0100
Open XML document...
Similar to the GLib Markup parser, which also just parses an xml subset, xml.c is a simple, small and self contained xml parser in one file. Ideal for embedding into other projects without the need for big external dependencies.