tests: add a BasicTestingSetup and apply to all tests

Make sure that chainparams and logging is properly initialized. Doing
this for every test may be overkill, but this initialization is so
simple that that does not matter.

This should fix the travis issues.

src/test/skiplist_tests.cpp

@@ -5,6 +5,7 @@
 #include "main.h"
 #include "random.h"
 #include "util.h"
+#include "test/test_bitcoin.h"
 
 #include <vector>
 
@@ -12,7 +13,7 @@
 
 #define SKIPLIST_LENGTH 300000
 
-BOOST_AUTO_TEST_SUITE(skiplist_tests)
+BOOST_FIXTURE_TEST_SUITE(skiplist_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(skiplist_test)
 {