Feature/factory additional/override helpers

[jakejohns]

How do people feel about the ability to pass additional/override helpers?

For example:

$my_helpers = [
    'foo' => $di->lazyNew(MyFooHelper::class),
    'url' => $di->lazyGetCall('radar/adr:router', 'newUrlHelper')
];

$Helper_locator_factory->newInstance($my_helpers);

[harikt]

@jakejohns not against passing helpers to factories.

[harikt]

Seems conflicts . Does this PR also contains things from recently merged PR #54 .

[jakejohns]

I rebased this branch. It should be happy now.

[harikt]

I am 👍 for this. Lets merge it.

[jakejohns]

@harikt if you like it, and @pmjones has no objection, I guess do it !