ExcitationFileHandler: remove unneeded parameter
ExcitationFileHandler: make ctor private

This prevents the singleton from being externally instantiated.
Remove unnecessary casts
Organize imports
Remove unnecessary semicolons
SLIMProcessor: remove unnecessary suppression
Fix leading and trailing whitespace
SLIMProcessor: widen type of global metadata field

This will allow us to move away from java.util.Hashtable later.
ExcitationFileUtility: remove unneeded parameter