Got rid of several unnecessary includes of <iostream>.

Including <iostream> causes the file to be polluted with a static
initializer for the __ioinit symbol. This can harm binary startup time.
For more info, see here:

    http://neugierig.org/software/chromium/notes/2011/08/static-initializers.html
diff --git a/include/json/assertions.h b/include/json/assertions.h
index 84eb5d7..2a22cc4 100644
--- a/include/json/assertions.h
+++ b/include/json/assertions.h
@@ -7,7 +7,6 @@
 # define CPPTL_JSON_ASSERTIONS_H_INCLUDED
 
 #include <stdlib.h>
-#include <iostream>
 
 #if !defined(JSON_IS_AMALGAMATION)
 # include <json/config.h>
@@ -18,7 +17,13 @@
 #define JSON_FAIL_MESSAGE( message ) throw std::runtime_error( message );
 #else  // JSON_USE_EXCEPTION
 #define JSON_ASSERT( condition ) assert( condition );
-#define JSON_FAIL_MESSAGE( message ) { std::cerr << std::endl << message << std::endl; exit(123); }
+
+// The call to assert() will show the failure message in debug builds. In
+// release bugs we write to invalid memory in order to crash hard instead of
+// calling exit(), so that a debugger or crash reporter gets the chance to take
+// over.
+#define JSON_FAIL_MESSAGE( message ) { assert(false && message); strcpy(reinterpret_cast<char*>(666), message); }
+
 #endif
 
 #define JSON_ASSERT_MESSAGE( condition, message ) if (!( condition )) { JSON_FAIL_MESSAGE( message ) }
diff --git a/include/json/reader.h b/include/json/reader.h
index 0a324df..a3023b3 100644
--- a/include/json/reader.h
+++ b/include/json/reader.h
@@ -13,7 +13,6 @@
 # include <deque>
 # include <stack>
 # include <string>
-# include <iostream>
 
 namespace Json {
 
diff --git a/include/json/writer.h b/include/json/writer.h
index 4789363..38d41e1 100644
--- a/include/json/writer.h
+++ b/include/json/writer.h
@@ -11,7 +11,6 @@
 #endif // if !defined(JSON_IS_AMALGAMATION)
 # include <vector>
 # include <string>
-# include <iostream>
 
 namespace Json {
 
diff --git a/src/lib_json/json_reader.cpp b/src/lib_json/json_reader.cpp
index e55745e..1f3873a 100644
--- a/src/lib_json/json_reader.cpp
+++ b/src/lib_json/json_reader.cpp
@@ -13,7 +13,6 @@
 #include <cstdio>
 #include <cassert>
 #include <cstring>
-#include <iostream>
 #include <stdexcept>
 
 #if _MSC_VER >= 1400 // VC++ 8.0
@@ -904,7 +903,14 @@
 {
     Json::Reader reader;
     bool ok = reader.parse(sin, root, true);
-    if (!ok) JSON_FAIL_MESSAGE(reader.getFormattedErrorMessages());
+    if (!ok) {
+      fprintf(
+          stderr,
+          "Error from reader: %s",
+          reader.getFormattedErrorMessages().c_str());
+
+      JSON_FAIL_MESSAGE("reader error");
+    }
     return sin;
 }
 
diff --git a/src/lib_json/json_value.cpp b/src/lib_json/json_value.cpp
index 3ba36fe..91f312e 100644
--- a/src/lib_json/json_value.cpp
+++ b/src/lib_json/json_value.cpp
@@ -12,7 +12,6 @@
 # endif // #ifndef JSON_USE_SIMPLE_INTERNAL_ALLOCATOR
 #endif // if !defined(JSON_IS_AMALGAMATION)
 #include <math.h>
-#include <iostream>
 #include <sstream>
 #include <utility>
 #include <stdexcept>
diff --git a/src/lib_json/json_writer.cpp b/src/lib_json/json_writer.cpp
index 47e768c..b44def3 100644
--- a/src/lib_json/json_writer.cpp
+++ b/src/lib_json/json_writer.cpp
@@ -11,7 +11,6 @@
 #include <assert.h>
 #include <stdio.h>
 #include <string.h>
-#include <iostream>
 #include <sstream>
 #include <iomanip>