Adds a new script file and the BUILD directory
Removes all YAML default values from Settings

I decided it would be better to die if we didn't have a value than to silently provide a default. This may get changed later to print defaulted key:value pairs to stderr (if it seems sensible)
Fixes C -> C++ inconsistency in handling empty structs
Fixes exposures type (was int, is double)
Adds command line handling to all applications

This necessitated a slight change in the way we handle settings in order to allow us to load a configuration file before the YAML file
Merge branch 'commandLineConfiguration' into develop
Merge branch 'commandLineConfiguration' into develop

Completes #7
Resets optind to allow multiple runs of getopt
Adds the Althaus WD models
Fixes where we call settings in sampleWDMass
Merge branch 'althausModel' into develop

Completes #1