Fix ROWNUM() in non-select commands and assorted minor changes in Condition implementations

Optimizing ConditionAndOr queries

Added test case

convert ((A=1 AND B=2) OR (A=1 AND B=3)) to (A=1 AND (B=2 OR B=3))
-Suggested changes in:
https://github.com/h2database/h2database/pull/1571#discussion_r235925138
https://github.com/h2database/h2database/pull/1571#discussion_r235925223

convert ((A=1 AND B=2) OR (A=1 AND B=3)) to (A=1 AND (B=2 OR B=3))

Add ANY, UNNEST, and fix SOME parsing

Defrag OOM

Refactor Expression implementations

Assorted minor changes