remapper: forgot an include in previous commit

7e215d0 remapper: now it remap also the openat syscall
remapper: normalize path before looking up in the mapping hash

sometime the loader can open a library using non normalized path
this will fail the lookup in the mapping hash.

e.g. if the loader try to open /opt/someapp/bin/../lib/libsomelib.so.0
and the mapping hash table contains /opt/someapp/lib/libsomelib.so.0
the lookup will fail
remapper: document some functions and remove duplicate import