Convert remaining comments in /src to doxygen format

- Update comments in checkpoints to be doxygen compatible
- Update comments in checkqueue to be doxygen compatible
- Update coins to be doxygen compatible
- Fix comment typo in crypter.h
- Update licenses/copyright dates

Closes #5325 #5184 #5183 #5182

src/db.h

@@ -1,6 +1,6 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2013 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Copyright (c) 2009-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_DB_H
@@ -50,7 +50,7 @@ public:
     void MakeMock();
     bool IsMock() { return fMockDb; }
 
-    /*
+    /**
      * Verify that database file strFile is OK. If it is not,
      * call the callback to try to recover.
      * This must be called BEFORE strFile is opened.
@@ -60,7 +60,7 @@ public:
                         RECOVER_OK,
                         RECOVER_FAIL };
     VerifyResult Verify(std::string strFile, bool (*recoverFunc)(CDBEnv& dbenv, std::string strFile));
-    /*
+    /**
      * Salvage data from a file that Verify says is bad.
      * fAggressive sets the DB_AGGRESSIVE flag (see berkeley DB->verify() method documentation).
      * Appends binary key/value pairs to vResult, returns true if successful.