Study manager

Administrator should be able to see new page "Statistics" accessible from dashboard.

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Content of the page:
Number of investigators   80   
Number of processed patients   108 

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Relevant queries:
SELECT (count(?p) as ?patientRecordsCount)
WHERE {
?p a <http://vfn.cz/ontologies/study-manager/patient-record> .
}

SELECT (count(?p) as ?investigatorCount)
WHERE {
?p a <http://vfn.cz/ontologies/study-manager/doctor> .
}