C# language binding generates C# method name beginning with verb by
checking verb list in name_helpers.hh.
Some verbs used in eo method are missing in the current verb list. So
they are added into the verb list.
In this scheme, there is a problem that some words can be used as a verb
in some methods but they also can be used as a noun in other methods.
(e.g. drag_start as a verb / cursor_word_start as a noun)
So "start" and "scroll" are not added to verb list in this patch.
To resolve the above problem, we may need a new eo syntax to rename or
reverse the name in language bindings.