fix #184: fix SQL syntax error in WITH ... UPDATE ... FROM

Merge pull request #183 from huandu/feature/select-lateral-derived-table

Support LATERAL keyword

Merge pull request #180 from huandu/bug/cond-misuse

Avoid stack overflow when Cond is misused

Merge pull request #175 from rodionovv/string-validation

Ignore empty content to prevent the output of incorrect SQL

fix #171: no need to escape field any more

reduce count of memory allocations in Cond.And/Or/Not

update docs in README and godoc

refs #164: new API SelectMore to add more cols to SELECT after callin…

…g Select()

fix: #160 SelectBuilder.With appends table names to FROM

Merge pull request #159 from abanoub-fathy/add-ILIKE-helper-method

Add ilike helper method