getLogPos() should return an int

git-svn-id: http://h2database.googlecode.com/svn/trunk@5053 e6896862-9d19-0410-bfb3-e9fa5d50e656
When the H2 parser fails to parse a SQL statement, throw a more specific exception that
contains extra information to make it possible for smart editors to do autocomplete.
Patch from Nicolas Fortin.

git-svn-id: http://h2database.googlecode.com/svn/trunk@5054 e6896862-9d19-0410-bfb3-e9fa5d50e656