CORE-1663: Support replaceIfExists for createView on H2

H2 supports CREATE OR REPLACE VIEW, so we can simply use the default case.

H2 documentation: http://www.h2database.com/html/grammar.html#create_view
Merge pull request #215 from siegi/replaceIfExistsH2

CORE-1663: Support replaceIfExists for createView on H2