parts dictionary for specifying recipe parts

[esben]

Combine the PACKAGES and FILES_{PN}, DEPENDS${PN}_ and so on variables of OE-lite into a common parts dictionary.

Each keys in parts corresponds to the entries in PACKAGES in OE-lite. The values are an object with attributes like files, `depends', and so on.

Something like:

parts = {}
parts[''].files = ['/bin', '/sbin', '/usr/bin', '/usr/sbin']
parts[''].depends = ['util-linux:uuid']
parts['doc'].files = ['/usr/share/doc']
parts['man'].files = ['/usr/share/man']
parts['libfoo'].files = ['/usr/lib/libfoo.so.*']
parts['libfoo'].depends = ['libc']
parts['libfoo-dev'].files = ['/usr/lib/libfoo.so', '/usr/lib/pkgconfig/libfoo.pc']
parts['libfoo-dev'].depends = [':libfoo']

Syntax for referencing other parts are then:

• foo - reference to default ('') part of foo recipe.
• foo:bar - reference to bar part of foo recipe.
• :bar - reference to bar part of current recipe.