Improve CI (#111)

build: Tea CI integration.

* build: Rename travis.sh to ci-build.sh
* build: Add .drone.yml for Tea CI
* README: Format as Markdown
* README: Add CI badges

.drone.yml

@@ -0,0 +1,6 @@
+build:
+        image: teaci/msys32
+        shell: mingw32
+        pull: true
+        commands:
+                - ./tools/ci-build.sh

.travis.yml

@@ -9,4 +9,4 @@ compiler:
   - gcc
   - clang
 
-script: ./tools/travis.sh
+script: ./tools/ci-build.sh

README.md

@@ -1,9 +1,16 @@
+| Platform | Status |
+| -------- | ------ |
+| Linux and Mac OS X | [![Build Status](https://travis-ci.org/concurrencykit/ck.svg)](https://travis-ci.org/concurrencykit/ck)
+| Windows | [![Build Status](https://tea-ci.org/api/badges/concurrencykit/ck/status.svg)](https://tea-ci.org/concurrencykit/ck) |
+
+```
   ____                                                        _  ___ _
  / ___|___  _ __   ___ _   _ _ __ _ __ ___ _ __   ___ _   _  | |/ (_) |_
 | |   / _ \| '_ \ / __| | | | '__| '__/ _ \ '_ \ / __| | | | | ' /| | __|
 | |__| (_) | | | | (__| |_| | |  | | |  __/ | | | (__| |_| | | . \| | |_
  \____\___/|_| |_|\___|\__,_|_|  |_|  \___|_| |_|\___|\__, | |_|\_\_|\__|
                                                       |___/
+```
 
 Step 1.
 	./configure

tools/ci-build.sh

@@ -1,6 +1,6 @@
 #!/bin/sh
 #
-# Skeleton for Travis integration testing.
+# Skeleton for continuous integration testing.
 ##############################################################################
 
 set -x