[Open-scap] Proposal: move duplicities from the individual libraries to a commnon place

[Lukas Kuklinek]

Hello,

As I'm going to redesign the interface of libraries that do not match openscap 
coding style standards (e.g. hidden data members of structures, iterators, 
and so on...) to do so, it would be nice to avoid duplicit work and/or 
copypasting the code :).

It would be helpful to move some parts of the code from the specific library 
directories (like OVAL, XCCDF, etc) into a new directory (named, 
say, 'common'). The directory would contain abstract data structures and 
tools any openscap library could internally use. Those include, but are not 
limited to:

* lists (like oval_collection or xccdf_list)
* hash table (or some other kind of an associative array)
* iterators
* C preprocessor macros for generating functions accessing data members
* any feature that tends to appear among several libraries

Suggestions and comments are welcome

Lukas Kuklinek