When generating rst files from xml class reference, unknown references
to operators were generated, as something like:
:ref:`operator <<class_Vector2_operator_lt_bool>`
was rendered in html as:
operator ( Vector2 right )
-it just needed escaping.
The small addendum checks for operator names containing '<' and
substitutes it with '\<', escaping at rst level and generating
instead the right rendered html:
operator < ( Vector2 right )
This affected mostly the reference pages of the VectorX family of
classes. If in the future more types need escaping, a more
general solution will be needed.