* Avoid lodash typecheks
Lodash is quite big project. Even with direct imports it loads [tons](https://github.com/knex/knex/pull/3804) of
code and still bloats node_modules. Especially since lodash mostly used
as a polyfill for modern features.
In this diff I attempted to reduce lodash usage by replacing type checks
with `typeof` operator which might be sufficient.
Also replaced lodash/isObject with custom simplified utility which does not
consider functions as objects and allows to simplify code in one place.
closes#1028
- add support for count(distinct *), avg(distinct *) and sum(distinct *)
- min and max don't really make sense with distinct, so didn't add those
Beefed up transaction implementation, still needs tests
and cleanup of nested transaction queues.
Left todo:
- Fix commented out tests
- Fix oracle driver's transactions
