Don't use GaudiAlg

[jmcarcell]

BEGINRELEASENOTES

• Change headers and add EventContext in algorithms not to use GaudiAlg
• Replace GaudiTool with AlgTool

ENDRELEASENOTES

[andresailer]

This is still work in progress or depend on some other PR?

[jmcarcell]

This should now be ready, finally the build is passing

[tmadlener]

Do I have to understand why AlgTool is the non-deprecated on while GaudiTool is? ;)

This looks fairly complete now, or is there still something missing?

[jmcarcell]

Do I have to understand why AlgTool is the non-deprecated on while GaudiTool is? ;)

GaudiTool is in GaudiAlg 😄
I think there are a few differences like AlgTool not accessing the data store directly. In general I think we use few things of the class and we could probably get by with a minimal implementation of IAlgTool.

This looks fairly complete now, or is there still something missing?

It's ready, I don't think anything needs to be changed unless we find issues but the tests are passing.