Add CONTRIBUTING.md with basic reStructuredText cheatsheet

CONTRIBUTING.md

@@ -0,0 +1,51 @@
+Contributing
+============
+
+Docstring Format
+----------------
+
+'The documentation style is [Sphinx' reStructuredText](http://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html). Here is an example demonstrating the most common syntax:
+
+```python
+def foo(a, b):
+    """
+    Short description of the function.
+
+    :param a: description of the parameter
+    :type a: the type of a parameter
+    :param int b: another syntax, for specifying the parameter's type and description together
+
+    :return: what the function returns
+    :rtype: the type the function returns
+
+    :raises TypeError: possible exception and when is it thrown
+
+    Longer description of the function, may contain multiple lines.
+
+    Italic is formatted with a single asterisk - *italic*.
+
+    Bold is formatted with a double asterisks - **bold**.
+
+    Inline code style is formatted with double backticks: ``identifier``.
+
+    Code blocks are formatted with the code-block directive and an indentation:
+
+    code-block::
+
+        assert foo(1, 1) == True
+
+    Or, you can add double colon at the end of a line to include a code block after that line::
+
+        assert foo(1, 2) == False
+
+    Example of interactive Python session that demonstrate the function are formatted with three greater-thans:
+
+    >>> foo(2, 2)
+    True
+
+    The interactive Python session formatting ends after one blank line
+    """
+    if type(a) is not type(b):
+        raise TypeError('a and b are not of the same type')
+    return a == b
+```

README.md

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 # easypy
 easypy makes python even easier!
+
+Contributers please read [CONTRIBUTING.md](CONTRIBUTING.md).