Fix weak keys so we can check the root certificate key length

Add documentation to Algorithms.scala
Fix the minimum key size to actually match what the NIST recommendations are.
Suppress the exception on a weak certificate in a default trust store to a warning.
Upgrade the keystore to use 2048 RSA key.
clean up log messages.
Make trust manager check trustanchor's keysize
Merge remote-tracking branch 'wsargent/fix-weak-keys-in-store'
Merge remote-tracking branch 'origin/master'