exceptions: Make Tlv::Error a base class for all packet-processing exceptions

This commit also includes a number of code style fixes.

Change-Id: I44f83915e733b43d5f43b4266902c8262e928d91
Refs: #1528
diff --git a/src/security/sec-tpm-memory.cpp b/src/security/sec-tpm-memory.cpp
index 3475aa4..393a217 100644
--- a/src/security/sec-tpm-memory.cpp
+++ b/src/security/sec-tpm-memory.cpp
@@ -20,7 +20,8 @@
 /**
  * RsaPrivateKey is a simple class to hold an RSA private key.
  */
-class SecTpmMemory::RsaPrivateKey {
+class SecTpmMemory::RsaPrivateKey
+{
 public:
   RsaPrivateKey(const uint8_t* keyDer, size_t keyDerLength)
   {
@@ -175,7 +176,7 @@
       rng.GenerateBlock(res, size);
       return true;
     }
-  catch (const CryptoPP::Exception& e)
+  catch (CryptoPP::Exception& e)
     {
       return false;
     }