first pass of updated minitaur quadruped environment

examples/pybullet/gym/pybullet_envs/minitaur/envs/timestamp.proto

@@ -0,0 +1,18 @@
+syntax = "proto3";
+
+package google.protobuf;
+
+message Timestamp {
+
+  // Represents seconds of UTC time since Unix epoch
+  // 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to
+  // 9999-12-31T23:59:59Z inclusive.
+  int64 seconds = 1;
+
+  // Non-negative fractions of a second at nanosecond resolution. Negative
+  // second values with fractions must still have non-negative nanos values
+  // that count forward in time. Must be from 0 to 999,999,999
+  // inclusive.
+  int32 nanos = 2;
+}
+