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/detail/pending-interest.hpp b/src/detail/pending-interest.hpp
index c481acc..c0a35e3 100644
--- a/src/detail/pending-interest.hpp
+++ b/src/detail/pending-interest.hpp
@@ -14,7 +14,8 @@
 
 namespace ndn {
 
-class PendingInterest {
+class PendingInterest
+{
 public:
   typedef function<void(const Interest&, Data&)> OnData;
   typedef function<void(const Interest&)> OnTimeout;