[2.0][RFC] Add get to default repository

[malarzm]

Today I have realized that most of my custom repositories are beginning with get method which looks just like the one I have here. So how about adding it to core? If we say "yes" then here's still few things to do like:

• change ObjectRepository occurrences to new Repository
• especially after rebasing odm-ng atop current master
• move PHPDocs to interface

Also since it's for 2.0 we may consider moving Repository-related classes around as we got ourselves "Repository" namespace just before 1.0, but that will mean more things to fix for users when upgrading.

[alcaeus]

As mentioned in IRC, I see a few issues with the method:

• We have find, findBy, findOneBy. Especially with find, it's not easy to understand the difference between find and get since they are not self-explanatory.
• One could argue that the current API covers the use cases. For those cases where the code can't continue if no object is returned, the code may as well throw the exception themselves and throw a specific exception instead of a generic DocumentNotFoundException.
• Last but not least, there's no comparable method in ORM and I don't know of any plans to add one. I'd always try to keep the APIs as comparable as possible, especially in those classes that don't deal with low-level logic that might depend on the database system in use.

Considering this, I'm 👎 on adding this.