Add PidDaoImpl to dao
Add PidDaoImpl to dao

This class implements PidDao and declares it as a bean so that the
latter of which can be turned into a Spring Bean.

HawaiiStateDigitalArchives/PID-webservice,Khyzad/PID-webservice,Khyzad/PID-webservice,HawaiiStateDigitalArchives/PID-webservice