Multi-Configuration/Multi-Installation to Built-ins

[ranelpadon]

Thanks for this awesome tool! :)

I usually have these use cases when working with our Python/Django projects:

• printing to terminal: ic() with context and custom prefix
• piping to logger: ic() without context and prefix

But currently, these 2 cases could not exist at the same time since configureOutput() is being applied on the same ic object.

Figured out that an effective solution is to have a way to create multiple instances of IceCream wherein each of them could have different configurations and could be added in builtins with different names (e.g. ic() and ik()):

• printing to terminal: ic() with context and custom prefix
• piping to logger: ik() without context and prefix

Hence, created this PR. I use the code changes here in our projects for some time already and it's working as intended. Likewise, updated the unit tests and README. Cheers!