[ISSUE] Add logger to colorable on fallBack

[SahilSainiYML]

Introduction

Our Colorable protocol helps users load (and unit test) colors from asset catalogs. It provides a fallback color to use in case the named color asset cannot be found. In that case though we should log a warning message.
Extract the code that builds name from namespace + rawValue into an internal calculateName() method and cover it in unit tests.
In ColorableTests try to minimize use of logger. Ideally log only one message before disabling the logging for remainder of failure cases

Purpose

Add logger to colorable protocol and add unit test for above scenarios.
Fix #55

Scope

Colorable protocol and Unit test for same protocol.

📈 Coverage

Code

100%

Documentation

100%

[mpospese]

Looks great. I updated the comments on the protocol and the default implementation so that the generated documentation looks good and does not have duplicates.