Oppa: add getInstance().

Agent\{Mysql,Pgsql}: optimize parseQueryError(), add TODO.

Profiler,Agent\Agent: optimize.

Result: update all result stuff to resource [change getResult()=>getR…

…esource()].

Query\Builder: fix unparenthesized ternary.

Link\Link,Link\Linker: optimize, update docs.

Agent\Agent: fix/update/optimize prepare & escape (and related) stuff…

…, add "?i" etc operators, add BuilderJsonTrait, add escapeName().

Query\Builder: fix/update/optimize where (and related) stuff, add prepareOp() and use in related stuff.
Query\BuilderTrait: fix esc(), fix/change escId() => escName(), drop field(),escField(), change identifier() => name().

Query\Builder: update/optimize prepareField().

Query\Builder: update/optimize limit,offset stuff.

Agent\Mysql,Pgsql: optimize parseQueryError().