Fixed broken compilation due to missing FALLOC_FL_PUNCH_HOLE

On RH7 machines need to do explicit include to 'linux/falloc.h' in order
to get all defines which are needed for fallocate(2) .
Execute-queus with multiple poped-elements
Major code refactoring: renames & reorder (fnx)

* Have single big lib (libfnx)
* Using modules perfixes (infra- core- serv- etc.)
* Changed lib-functions name-prefix to 'fnx_'
* Moved user-syscalls to be part of libfnx with 'fns_' prefix
* Compile apps-common into libfnxapp

Signed-off-by: Shachar Sharon <shachars@xxxxxx>
Disabled on-disk checksuming (no-fnv)
Change lib's pp-gaurd prefix to FNX_