fixes #3252

also improved unit tests for querybuilder buildLikeCondition

issue #2852

Fixes #2571: Fixed the bug that batchInsert will fail for SQLite if the values contain null or boolean false;
Fixes #2683: Fixed the bug that batchInsert will fail for MySQL if the values contain boolean false.

Improved `QueryBuilder::buildLimit()` to support big numbers

Change <code>array_reduce</code> with anonimous function variant to easy string collection from pieces of unions.

Change buildUnion method to be ready to accept parameters in <code>['all' => $all, 'query' => $query]</code> format for division to "UNION" and "UNION ALL" constructions.

Delete some spaces from result string.

Fixed some errors – syntax with ";" after closure function and also moved building of unions queries into this function.

Change using of implode to convert array of queries to union to array_reduce. Result of this changing is that code feel difference between two selects that connects with UNION and two selects that connects with UNION ALL.

Fixes #1586: `QueryBuilder::buildLikeCondition()` will now escape special characters and use percentage characters by default

issue #1523

this allows us to implement other activerecord implementations based on
NoSQL dbms