Merge branch 'GAUDI-1078' into 'master'

GAUDI-1078: include caller algorithm name in messages from public tools

Using a feature developed in the LHCb software update the Error, Warning and
Info method for tools that inherit from GaudiTool to, when created as public
tools (defined by ultimately being owned by the ToolSvc) to append the current
active algorithm name to the end of each method.

So for instance if a private tool would print

    TestToolAlg.ToolC    INFO TestTool:: test info

a public instance instead prints

    ToolSvc.ToolB        INFO TestTool:: test info [TestToolAlg]

This feature has proved very useful in applications where a very large number
of algorithms all use the same public tools, as it allows problems associated
with what the caller is doing to be much more easy isolated.

Closes GAUDI-1078.

See merge request !40