Add clearance number

[nutjob4life]

Please add the clearance number to the footer of every page of KSDB.

It should have the following items in the footer:

• Site Manager: Dan Crichton
• Webmaster: David Liu
• Clearance: CL № 23-1970

[yuliujpl]

Done on the ddsa url! It's a bit ugly right now but content is there!

[nutjob4life]

Oh woops, I should've mentioned: this clearance number is valid only for https://mcl.jpl.nasa.gov/ksdb, not ddsa. We don't have a clearance for DDSA KSDB