Initial s390-tools-2.0.0 import

This commit is based on the s390-tools-1.39.0 version.

Changes on top of s390-tools-1.39.0:

 - Add MIT license to all source files
 - Add LICENSE file
 - Transform REAMDE to README.md (markdown)
 - Add AUTHORS.md file
 - Add CONTRIBUTING.md file
 - Move changelog from README to CHANGELOG.md file

Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>

zdev/include/opts.h

@@ -0,0 +1,29 @@
+/*
+ * zdev - Modify and display the persistent configuration of devices
+ *
+ * Copyright IBM Corp. 2016, 2017
+ *
+ * s390-tools is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#ifndef OPTS_H
+#define OPTS_H
+
+#include "exit_code.h"
+
+#define OPTS_MAX	255
+#define OPTS_CONFLICT(x, ...)    { .op = (x), \
+				  .conflicts = ((int []) { __VA_ARGS__, 0 })}
+
+struct opts_conflict {
+	int op;
+	int *conflicts;
+};
+
+struct option;
+
+exit_code_t opts_check_conflict(int, int[OPTS_MAX + 1], struct opts_conflict *,
+				const struct option *);
+
+#endif /* OPTS_H */