cf-agent --bootstrap fails on Debian systems.

Because sys.workdir/inputs is a symlink to /etc/cfengine3. The bootstrap process creates ```failsafe.cf``` in /etc/cfengine3, but cf-agent complains that this sys.workdir/inputs is a symlink and aborts the bootstrap process. Both must fail/complain or both must accept the symbolic link to the directory as destination.

This patch enable the last option. It will determine if the destination is a symlink to a directory and ```copy_from``` attribute ```type_check : false``` is set.  If both options are true the copy will be honored.