*.pl: switch to use lib "__BASEDIR__";

*.pl: switch to use lib "__BASEDIR__";

Change all the old-style use lib lines that try to locate the
Girocco::* files to use "__BASEDIR__" instead.

The ones using @basedir@ (or "@basedir@") could not even be
syntax checked without first installing them.

The ones using "." are unnecessary (unless there's a "Girocco"
somewhere in the default Perl search path) and present an extended
attack surface if the current directory can be successfully changed.

The ones using dirname($0) require a symbolic link in the same
directory as the script and require $0 to be accurate.  Both of
which are less than optimal choices.

Instead switch to the newly supported "__BASEDIR__" which mostly
just works in a non-installed repository.  For convenience when
working with a cwd set to cgi, jobd, taskd or toolbox make sure
there is a suitable symbolic link in there from Girocco to ../Girocco
to facilitate development.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>