[Core] Start renaming BaseObject to BaseComponent

[alxbilger]

A not-working PR to start the discussion on renaming BaseObject to BaseComponent. It makes more sense for me as we name the classes in the factory 'Component'.

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Reviewers will merge this pull-request only if

• it builds with SUCCESS for all platforms on the CI.
• it does not generate new warnings.
• it does not generate new unit test failures.
• it does not generate new scene test failures.
• it does not break API compatibility.
• it is more than 1 week old (or has fast-merge label).

[damienmarchal]

PR accepted

[bakpaul]

The CI says otherwise...

[alxbilger]

Agreed during the dev meeting

[alxbilger]

A lot of BaseObject usages relied on a using declaration (using sofa::core::objectmodel::BaseObject). It means one of this using declaration in a header contaminated a large part of the code base. I took the opportunity to remove all the using declaration of BaseObject. This makes this PR breaking, more than the renaming.

For example, the following code used to compile:

template<class T>
class DummyComponent : public BaseObject
{
public:
    SOFA_CLASS(DummyComponent<T>, BaseObject);
};

but the following is working with the compatibility:

template<class T>
class DummyComponent : public core::objectmodel::BaseObject
{
public:
    SOFA_CLASS(DummyComponent<T>, core::objectmodel::BaseObject);
};