included-tests: generate binary data from test files for inclusion into test binaries

This change moves test data into the binaries rather than reading them from
the disk at runtime.

Advantages:
- Tests become distributable
- Cross-compile friendly. Build on one machine and execute in an arbitrary
  location on another.
- Easier testing for backports. Users can verify that tests pass without having
  to track down corresponding test data.
- More trustworthy test results and easier quality assurance as tests make
  fewer assumptions about their environment.
- Tests could theoretically run at client/daemon startup and exit on failure.

Disadvantages:
- Required 'hexdump' build-dependency. This is a standard bsd tool that should
  be usable everywhere. It is likely already installed on all build-machines.
- Tests can no longer be fudged after build by altering test-data.

src/test/transaction_tests.cpp

@@ -5,12 +5,14 @@
 
 #include "main.h"
 #include "wallet.h"
+#include "data/tx_invalid.json.h"
+#include "data/tx_valid.json.h"
 
 using namespace std;
 using namespace json_spirit;
 
 // In script_tests.cpp
-extern Array read_json(const std::string& filename);
+extern Array read_json(const std::string& jsondata);
 extern CScript ParseScript(string s);
 
 BOOST_AUTO_TEST_SUITE(transaction_tests)
@@ -22,7 +24,7 @@ BOOST_AUTO_TEST_CASE(tx_valid)
     // Inner arrays are either [ "comment" ]
     // or [[[prevout hash, prevout index, prevout scriptPubKey], [input 2], ...],"], serializedTransaction, enforceP2SH
     // ... where all scripts are stringified scripts.
-    Array tests = read_json("tx_valid.json");
+    Array tests = read_json(std::string(json_tests::tx_valid, json_tests::tx_valid + sizeof(json_tests::tx_valid)));
 
     BOOST_FOREACH(Value& tv, tests)
     {
@@ -91,7 +93,7 @@ BOOST_AUTO_TEST_CASE(tx_invalid)
     // Inner arrays are either [ "comment" ]
     // or [[[prevout hash, prevout index, prevout scriptPubKey], [input 2], ...],"], serializedTransaction, enforceP2SH
     // ... where all scripts are stringified scripts.
-    Array tests = read_json("tx_invalid.json");
+    Array tests = read_json(std::string(json_tests::tx_invalid, json_tests::tx_invalid + sizeof(json_tests::tx_invalid)));
 
     BOOST_FOREACH(Value& tv, tests)
     {