Enforcing CLAM's framework good practices.

Another change related with the Processing infrastructure 3.2.2 is the clarification of a single way of doing things, removing accessory behavior that has not proven as useful as expected. In the first phases of the framework design, there were obvious problems of ``over-design'', which resulted in offering different ways of doing similar things. This flexibility promotes misuse and unnecessary complexity. There are now many Processing classes and in some cases some of them do similar things such as type checking or default initialization in different ways. A clear guideline in how all Processing objects should behave has been issued but now needs to be promoted into the whole repository.

• Cleaning up and clarifying of Processing interface. The goal is to remove all unnecessary interface and enforce the strict use of some design principles for all CLAM users developing their own Processing class.
• Cleaning up duplicated, old fashioned or unused code around CLAM and CLAM examples.
• Testing has been already introduced in the framework and is spreading at a steady state. Both unit tests and functional tests are compiled and run on a daily basis and help ensure the framework stability and confidence. Nevertheless, a lot has to be done in order to have a well-covered framework. The goal is to extend the test coverage to most of the CLAM code, and enhancing the test infrastructure in order to be easier for the processing writers to do their own testing.