[API] Fix Monitoring limits

Set reasonable limits for delay/timeout (0 < x <= 3600) and path length (2000).

Change-Id: Icc6225363eef017c31dc615c3a4870d2f2ba8829
[API] URL Encode the URLs supplied for health monitoring

Follows RFC3986 allowed chars, encodes everything else but also includes
'%' to stop double-encoding

Change-Id: I07d925937b20a30d1f1fc1a79801d4c6f823e22c