Rationalize logging statements across codebase

This fixes up the following problems:
1. Using string concatenation instead of the formatting variant methods.
2. Logging or swallowing exception messages without logging the exception
   itself (this swallows the stack trace).
3. Unnecessary logging on re-thrown exceptions.
4. Unnecessary use of formatting variant methods when not necessary.
5. Complicated logging statements involving significant processing not being
   wrapped inside of a logging level check.
6. Redundant logging both of an exception itself and its message (this is
   unnecessary duplication).
7. Use of the base Logger class instead of our FormattingLogger class.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182419837

java/google/registry/flows/EppXmlTransformer.java

@@ -130,7 +130,8 @@ public class EppXmlTransformer  {
       try {
         byte[] lenient = EppXmlTransformer.marshal(eppOutput, LENIENT);
         // Marshaling worked even though the results didn't validate against the schema.
-        logger.severe(e, "Result marshaled but did not validate: " + new String(lenient, UTF_8));
+        logger.severefmt(
+            e, "Result marshaled but did not validate: %s", new String(lenient, UTF_8));
         return lenient;
       } catch (XmlException e2) {
         throw new RuntimeException(e2);  // Failing to marshal at all is not recoverable.