remove unused UT code

• remove use of detType() (which should always return "UT")
• remove readout tool template argument which is always IUTReadoutTool
• remove setForcedInit() form CommonBase which is now the only option
• remove use of stringToType, directly use the corresponding rawbank type enum instead
• remove unused setDetType which is only ever set to UT
• remove unnecessary mutable qualifiers

must be applied in conjunction with Lbcom!521 (merged), Rec!2281 (merged) and Boole!326 (merged)