Added coroutine related exception class [WIP]

python/common/org/python/exceptions/asyncio/InvalidStateError.java

@@ -0,0 +1,10 @@
+package org.python.exceptions.asyncio;
+
+/**
+ * The operation is not allowed in this state.
+ */
+public class InvalidStateError extends org.python.exceptions.concurrent.Error {
+    public InvalidStateError(java.lang.String msg) {
+        super(msg);
+    }
+}

python/common/org/python/exceptions/concurrent/CancelledError.java

@@ -0,0 +1,10 @@
+package org.python.exceptions.concurrent;
+
+/**
+ * The Future was cancelled.
+ */
+public class CancelledError extends org.python.exceptions.concurrent.Error {
+    public CancelledError() {
+        super();
+    }
+}

python/common/org/python/exceptions/concurrent/Error.java

@@ -0,0 +1,14 @@
+package org.python.exceptions.concurrent;
+
+/**
+ * Base class for all future-related exceptions.
+ */
+public class Error extends org.python.exceptions.Exception {
+    Error() {
+        super();
+    }
+
+    public Error(java.lang.String msg) {
+        super(msg);
+    }
+}

python/common/org/python/exceptions/concurrent/TimeoutError.java

@@ -0,0 +1,10 @@
+package org.python.exceptions.concurrent;
+
+/**
+ * The operation exceeded the given deadline.
+ */
+public class TimeoutError extends org.python.exceptions.concurrent.Error {
+    public TimeoutError() {
+        super();
+    }
+}