[SP-902]  backport of [MONDRIAN-1819] Mondrian generates timestamp predicates for date fields.

This is an issue specific to the Oracle jdbc driver ojdbc5 and above, which treats the DATE datatype as a TIMESTAMP. Because of this, dates can have a value like
'2001-01-19 00:00:00.0', which cannot be used as a DATE literal. This change to OracleDialect.quoteDateLiteral() assures date literals conform to the ANSI spec.
(cherry picked from commit 180f83a)
Merge pull request #235 from mkambol/3.6mon1819b

[SP-902]  backport of [MONDRIAN-1819] Mondrian generates timestamp predi...