(*) Implement CMAlgoArray
    - Inherits from CMergeAlgoBase (i.e. can be attached to CMergeManager)
    - Handles a vector of merging algorithms with AND/OR configuration
    - This replaces what CMergeManager was doing (i.e. CMergeManager no longer handles a collection of merging algorithm)
    - Above is an ideal scheme: a collection of algorithm with AND/OR configuration is itself an algorithm... so it should have been implemented like CMAlgoArray from the beginning

(*) Related modifications in CMergeManager and python scripts.

Kazu