Fix link to 'fifth leg of the tour' in 'Tour of Ceylon: Type aliases and type inference'

http://ceylon-lang.org/documentation/1.0/tour/typeinference/#member_class_aliases_and_class_alias_refinement
Merge pull request #267 from olivergondza/typeinference-link

Fix link to 'fifth leg of the tour' in 'Tour of Ceylon: Type aliases and type inference'