GitLab

• In the TROTs dataset sometimes the entry exists but is empty. For example the Protons_01/rtplan.dcm TableTopVerticalPosition exists but is None. Inserted an additional check to see if the entry is empty
• dcm::InstanceNumber was commented as optional but code was crashing if it was present, as it was missing a has condition

Minor change:

• Institute name was commented as optional but in our case its mandatory cus we don't provide institute serial number