ENH: Extensibility improvements (Injector use, avoid private methods).

[mfendeksilverstripe]

ENH: Extensibility improvements (Injector use, avoid private methods).

• improve Injector use
• avoid private methods so the code is more extensible

[mfendeksilverstripe]

@chrispenny Can you please review this one?

[chrispenny]

@mfendeksilverstripe do you need to extend those methods at the moment?

The reason to use private is to reduce the size of the API. A smaller API means we're less like to cause "breaking changes" if we happen to want to remove/refactor one of those private methods.

[mfendeksilverstripe]

I don't need to open up these methods ATM. Can change them back to private @chrispenny

[mfendeksilverstripe]

@chrispenny I've reverted the method visibility change, please review.