Travis migration (#1517)

* Rolled back Travis stages

* Rolled back the rolled-back changes.

* Renamed jobs, coverage can no longer fail.

* Cleaned up the yaml file a bit.

* Updated coveralls badge.

.travis.yml

@@ -15,29 +15,26 @@ jobs:
   # --elopio - 20180531
   fast_finish: true
   allow_failures:
-    - env: SOLIDITY_COVERAGE=true
     - env: SOLC_NIGHTLY=true
   include:
-    # Run the unit test suite three times in parallel.
-    # The first one gets results faster and is the only one required to pass.
-    # The second one generates the coverage report.
-    # The third one is to keep us informed about possible issues with the
-    # upcoming solidity release.
     - stage: tests
-      name: "unit tests"
+      name: "Linter"
+      script: npm run lint
+
+    - stage: tests
+      name: "Unit tests"
       script: npm run test
+
     - stage: tests
-      name: "unit tests with coverage"
+      name: "Unit tests with coverage report"
       script: npm run test
       env: SOLIDITY_COVERAGE=true
+
     - stage: tests
-      name: "unit tests with solc nightly"
+      name: "Unit tests using solc nightly"
       script: npm run test
       env: SOLC_NIGHTLY=true
-    # solidity and javascript style tests.
-    - stage: tests
-      name: "static tests"
-      script: npm run lint
+
     - stage: update docs
       if: tag =~ ^v[0-9]+\.[0-9]+\.[0-9]+$
       addons:

README.md

 # <img src="logo.png" alt="OpenZeppelin" width="400px">
 
 [![NPM Package](https://img.shields.io/npm/v/openzeppelin-solidity.svg?style=flat-square)](https://www.npmjs.org/package/openzeppelin-solidity)
-[![Build Status](https://img.shields.io/travis/OpenZeppelin/openzeppelin-solidity.svg?branch=master&style=flat-square)](https://travis-ci.org/OpenZeppelin/openzeppelin-solidity)
-[![Coverage Status](https://img.shields.io/coveralls/github/OpenZeppelin/openzeppelin-solidity/master.svg?style=flat-square)](https://coveralls.io/github/OpenZeppelin/openzeppelin-solidity?branch=master)
+[![Build Status](https://travis-ci.com/OpenZeppelin/openzeppelin-solidity.svg?branch=master)](https://travis-ci.com/OpenZeppelin/openzeppelin-solidity)
+[![Coverage Status](https://coveralls.io/repos/github/OpenZeppelin/openzeppelin-solidity/badge.svg?branch=master)](https://coveralls.io/github/OpenZeppelin/openzeppelin-solidity?branch=master)
 
 **OpenZeppelin is a library for secure smart contract development.** It provides implementations of standards like ERC20 and ERC721 which you can deploy as-is or extend to suit your needs, as well as Solidity components to build custom contracts and more complex decentralized systems.