Introduce the notion of GenerateInitInstanceLocal which is static

and used explicitly in the current dictionary.  This allow proper support for
a configuration where MyVector<double> AND MyVector<Double32_t> both
have a dictionary (since the lookup is by C++ signature, only one
of the GenerateInitInstance can be exported per se thus the need to
disambiguate)


git-svn-id: http://root.cern.ch/svn/root/trunk@14840 27541ba8-7e3a-0410-8455-c3a389f83636