#57 - Added CONTRIBUTING.md with info about tests and PRs.

CONTRIBUTING.md

@@ -0,0 +1,77 @@
+## Pull Requests
+
+All changes, no matter how trivial, must be done via pull request. Commits
+should never be made directly on the `develop` branch. Prefer rebasing over
+merging `develop` into your PR branch to update it and resolve conflicts.
+`master` branches are for releases only.
+
+In addition, you must follow these rules
+
+1. Create an issue before creating a PR where you describe the problem. Your issue should
+be limited to only one problem.
+
+2. All PR commits must reference an issue and provide a brief commit message about the commit.
+Here is an example
+```
+#123456 - Fixed an issue with unhanded client errors.
+
+```
+
+## Tests
+
+When writing a unit test, please be sure to follow these rules.
+
+1. You test has this structure
+
+    ```
+    expect{
+          ClassYouAreTesting().value()
+    }.To(
+          expectedValue,
+         "Description of the test intention.
+          (e.g. "Returned value must be in the 1..5 range.")"
+      )
+    ```
+
+    However, test failure description is not necessary,
+    if the class you are testing implements the `Error` protocol.
+
+2. If you are creating fake classes/decorators for a test, make sure
+    that these classes are named as `FakeXXXX`.
+
+3. The usage of the setUp() and tearDown() methods is prohibited.
+
+4. The tests must not share any test values, such as sample input values.
+   The only exception is the test resources, like directory path or test API URL.
+   (These must be structured according to test rule #3)
+
+   See [this](http://www.yegor256.com/2016/05/03/test-methods-must-share-nothing.html) for more information.
+
+5.  Your test has proper documentation, which explains what class it is testing
+    in the format specified below
+
+    ```
+    //
+    // This source file is part of the Web3Swift.io open source project
+    // Copyright 2018 The Web3Swift Authors
+    // Licensed under Apache License v2.0
+    //
+    // ClassNameTest.swift
+    //
+    // Created by FirstName LastName on DD/MM/YYY
+    //
+    ```
+
+6.  The name of the unit test source file has to follow this structure
+
+    ```
+    ClassNameTest.swift
+    ```
+
+7.  The name of the integration test source file has to follow this structure
+
+    ```
+    ClassNameIT.swift
+    ```
+
+

Example/Web3Swift.xcodeproj/project.pbxproj

@@ -177,6 +177,7 @@
 				50C3ECB5548832459AC51D59 /* Pods */,
 				B8B89B3A7E7096470B1FDD04 /* Frameworks */,
 				584FAC786109413F2D9921CE /* Extensions */,
+				C2E095FBE1BB2235A75CDA84 /* CONTRIBUTING.md */,
 			);
 			sourceTree = "<group>";
 		};