updates to OSS-Fuzz integration

adapt more fuzz targets from zlib,
add zip fuzzer, zip dictionary.
update uncompress_fuzzer to seed the buffer length separately.

tests/uncompress2_fuzzer.c

@@ -0,0 +1,20 @@
+/* Derived from zlib fuzzers at http://github.com/google/oss-fuzz/tree/master/projects/zlib,
+ * see ossfuzz.sh for full license text.
+*/
+
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "miniz.h"
+
+static unsigned char buffer[256 * 1024] = { 0 };
+
+int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
+{
+    unsigned long int buffer_length = sizeof(buffer);
+
+    if (Z_OK != uncompress2(buffer, &buffer_length, data, &size)) return 0;
+    
+    return 0;
+}