Composite catalog implementation

[mantid-builder]

Original Reporter: Jay Rainey

This ticket is blocked by :

• TRAC9069

This ticket is blocks : TRAC7640, TRAC9084

== Implementation ==

There needs to exist support for multiple catalogs within Mantid, which can be achieved via a composite pattern.

1. A new class (CompositeCatalog) needs to be created.
2. This class will hold a list of ICatalog instances (shared pointers) named m_catalogs.
3. Catalogs can be added to m_catalogs using an add() method.
4. The class will inherit from ICatalog and override all the parents methods.
5. Each method will iterate over m_catalogs and call the exact method from the catalog.

== Unit test ==

A test class needs to be created for this composite class to verify the functionality works as expected.

1. Create a test class (CompositeCatalogTest).

2. Create a DummyCatalog class within the test class that extends ICatalog and then overrides all methods (to verify that each work).

3. Have a static counter in each method, in order to verify when they are called.

4. Create a test method for each ICatalog method.

5. Create several (3-5) DummyCatalogs in each method, and call the related ICatalog method, verifying that the counter increased as expected.

   Keywords: ICAT

[mantid-builder]

This issue was originally trac ticket 9026