* add frontend interfaces to file to get a mmaping
* SECTION macro to encapsulate mmap access
* mmap_address() translating an actual offset to address
* add some tests
* some test cosmetics
Quite some code which was hold back in favor of the config and plugin stuff
implements:
* mmapcache: mru cache for unused memory mappings
* mmap: single mmaped areas
* mmapings: manages mmaps established for one filedescriptor
