Remove default exceptions
Remove default exceptions

Since we now have the --exceptions-file option and use this tool
in different projects, remove the default values that apply only to
openstack-manuals. A patch to use --exceptions-file has been submitted
for openstack-manuals.

Change-Id: I2d5116ace29d832f39fa3ea6560e187a14521d64

openstack/openstack-doc-tools,savinash47/openstack-doc-tools,savinash47/openstack-doc-tools,openstack/openstack-doc-tools,savinash47/openstack-doc-tools