The CASTOR/SHIFT function sstrerror_r() should call the "standard"
function strerror_r().  Before this modification the "standard"
strerror() function was being called which is not guranteed to be
thread safe.

Compiling the CASTOR/SHIFT function sstrerror_r() code as C++ code
as opposed to C code makes the GNU compiler check the return type
of the "standard" function strerror_r().

The return type of the "standard" function strerror_r() is char *
for the GNU version and int for the POSIX version.

The following two conditions must be true in order to use the
POSIX version of strerror_r():

1. _GNU_SOURCE must NOT be defined
2. Either _XOPEN_SOURCE should be defined as 600 or
   _POSIX_C_SOURCE should be defined as 200112L

Clang was clever enough to know that just setting it does not mean
that it is used.

Do not link with debug, bfd, iberty and z library when not compiling in debug mode. These are useless in that case

The sstrerror() function was developed in CASTOR to deal with SHIFT
error codes as well as standard errno error codes.  The sstrerror()
was also supposed to be thread safe.  I believe that this is not the
case and if I am right then it will be fixed for all of CASTOR in a
later commit.

The CASTOR executables are not running short of CPU cycles.  The extra
effort required to debug released binaries compiled with the -O2
option is therefore not justified.

This was failing in SLC5. The default is now 0/0 insteadof
-1/-1  for major/minor in the device list.

Added support for TPconfig, looking for drive and density.
Improved logging and error situations handling.

This is achieved with an extra setup function.

We now support a new "model" of drives called virtual. This will allow
auto-detection of drives in fake environement, for unit tests.
Changed accordingly the signature of the reference returned by the Drive
wrapper from DriveGeneric to DriveInterface
Also fixed the order of the parameters of setDensityCode, to allow the usage
of the default densityCode.

Added a small section on how-to compile catsor on SLC and possible issues which can be faced while doing so

Exception is now catch by const-ref instead of a copy, message has been improved and move from string::find to string::substr to make sure the file is well formated

The DriveCatalogue::enterDrive() method has been superseded by the
DriveCatalogue::populateCatalogue() method.  I have therefore
removed the now unused DriveCatalogue::enterDrive() method.

The contents of the tape drive catalogue can now be populated by
passing it the parsed lines of /etc/castor/TPCONFIG.

We are now using the matching files and classes frpm castor/tape/threading

One was requiered because castor::tape::Exception asks for std::string in his constructor