Define accepted log public keys about certificatetransparency HOT 2 OPEN

We also need to check what key algs our compliance monitoring infrastructure supports to provide the minimal set of supportable key types.

from certificatetransparency.

Also, of note is Section 2.1.4 of RFC 6962 which states:

Various data structures are signed. A log MUST use either elliptic
curve signatures using the NIST P-256 curve (Section D.1.2.3 of the
Digital Signature Standard [DSS]) or RSA signatures (RSASSA-PKCS1-
V1_5 with SHA-256, Section 8.2 of [RFC3447]) using a key of at least
2048 bits.

from certificatetransparency.