Patient reports billing to include specimen ID
included getSpecimenId under class patient to get specimen id
Display message if no test is selected or there are not tests
added a function getSpecimenId in patient class to get speciment id for
patient report billing.
Added getSpecimenId function to get specimenid for the reports_billing
Merge branch 'master' of github.com:I-TECH/KenyaLIS

Conflicts:
	htdocs/billing/bill_review.php
	htdocs/includes/db_lib.php
	htdocs/reports/reports_billing.php