Remove the useage of StatusCode

[Nick Draper]

This is a hangover from GAUDI code and should be removed and replaced by throwing exceptions.

[Dickon Champion]

(In [503]) init/initialise() exec/execute() final/finalize() are all now void functions AnalysisDataService functions add/addOrReplace/retrieve/remove() are also now void functions all these functions throw exceptions and have been put in try/catch loops where appropriate, sometimes they add to the logger sometimes they do not

refs #69

[Dickon Champion]

(In [504]) init/initialise() exec/execute() final/finalize() are all now void functions AnalysisDataService functions add/addOrReplace/retrieve/remove() are also now void functions all these functions throw exceptions and have been put in try/catch loops where appropriate, sometimes they add to the logger sometimes they do not

refs #69

[Dickon Champion]

(In [505]) init/initialise() exec/execute() final/finalize() are all now void functions AnalysisDataService functions add/addOrReplace/retrieve/remove() are also now void functions all these functions throw exceptions and have been put in try/catch loops where appropriate, sometimes they add to the logger sometimes they do not

refs #69

[Dickon Champion]

(In [506]) init/initialise() exec/execute() final/finalize() are all now void functions AnalysisDataService functions add/addOrReplace/retrieve/remove() are also now void functions all these functions throw exceptions and have been put in try/catch loops where appropriate, sometimes they add to the logger sometimes they do not

refs #69

[Dickon Champion]

(In [507]) init/initialise() exec/execute() final/finalize() are all now void functions AnalysisDataService functions add/addOrReplace/retrieve/remove() are also now void functions all these functions throw exceptions and have been put in try/catch loops where appropriate, sometimes they add to the logger sometimes they do not

refs #69

[Nick Draper]

(In [510]) re #69 correct catch order to remove warning

[Dickon Champion]

(In [512]) changed order of catch statement refs #69

[Dickon Champion]

(In [513]) changed order of catch statement refs #69

[Dickon Champion]

(In [514]) input workspace not a full failure if not retrieved in Algorithm::execute() refs #69

[Dickon Champion]

(In [515]) tests for affected algorithms updated after status code change refs #69

[Dickon Champion]

(In [516]) further tests updated after status code change refs #69

[Russell Taylor]

(In [522]) No need for return from ADS::retrieve to be by reference argument now that StatusCode is no more. Re #69.

[Dickon Champion]

(In [525]) final removal of all StatusCode references refs #69

[Russell Taylor]

(In [526]) Removed StatusCode.h include from HelloWorldAlgorithm. Re #69.

[Stuart Campbell]

This ticket has been transferred to github issue ​917