[REF] [Import] Activity - clean up copy & paste

[eileenmcnaughton]

This class has a lot of handling for error codes but the 2 functions called

• import() and summary() only error return valid or error - the rest of this handling is simply copy and paste
  from the contact import - which does indeed handle conflicts and duplicates and record them

Although there is handling for a function called internally to return a conflict this is converted to an error...

Note that the activity import does not off the option of duplicate handling - which is the context in which these error types are used in the contact import

[civibot]

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[yashodha]

@eileenmcnaughton Can you please resolve the conflicts for this one?

[eileenmcnaughton]

thanks @yashodha - it's rebased now

[yashodha]

@eileenmcnaughton looks good,merging this.

[eileenmcnaughton]

thanks @yashodha