Data integrity checking and block self-healing:

 Add a CRC32C at the storage level to detect any error from
 the local file system (either software or hardware).

 Self-healing of the block(s) for which a CRC error has been detected.
 This takes place at the end of a read transaction on the client side.

 The control of the CRC32C configuration is defined within the
 storaged configuration file:

 example:
   #Linux debian 3.2.0-4-amd64 #1 SMP Debian 3.2.51-1 x86_64 GNU/Linux
   #05-12-2014-20:02:51
   threads = 3;
   nbCores = 4;
   crc32c_check = false;
   crc32c_generate = true;
   crc32c_hw_forced = false;

   storio  = "single";listen = (
     {addr = "192.168.2.1"; port = 41000;} ,
     {addr = "192.168.3.1"; port = 41000;}
   );
   storages = (
     {cid = 1; sid = 1; root ="/home/rozofs/rozofs-master/tests/storage_1-1";}
   );

 Tree new parameters have been defined:
 crc32c_check,crc32c_generate and crc32c_hw_forced.

 crc32c_hw_forced: that boolean can be asserted if the information
 reported by cpuid does not indicates that hardware CRC is supported
 whilst the current CPU supports it.(this might be the case with VirtualBox).

 New statistics:
 STORAGED:
 ________
 - data_integrity:
    show the current connfiguration and the number of CRC errors
     - Data integrity :
     crc32c generation      : ENABLED
     crc32c control         : DISABLED
     crc32c computing mode  : SOFTWARE
     crc32c error counter   : 0

 - profiler/diskThreads:
    add a new field (repair) to address the case of the self healing

 STORCLI:
 ________
  - profiler :
    add a bunch of counters related to the self-healing:
      repair
      repair_prj
      repair_prj_tmo
      repair_prj_err