Shared-memory communication can be disabled through cmake
compile time option `-DUSE_SHM:BOOL=OFF`

Refactored initialization code.

 - More detailed logging
 - Use exceptions to better propagate errors
 - Log signal type before shutdown

Daemon is now capable of providing version information through the
`--version` cli option.

Get rid of all the occurrences of old project name "adafs" from output
strings and documentation

ADAFS_CWD -> GKFS_CWD

get rid of old adafs name from pid file

`adafs_preload_client` -> `gkfs_intercept`

`adafs_daemon` -> `gkfs_daemon`