Adding Travis CI and Coveralls support

tool/travis.sh

+#!/bin/bash
+
+# Fast fail the script on failures.
+set -e
+
+function clean {
+  # This is a much more simple clean script, assuming git is available
+  pushd test
+  git clean -fdx

[Siggi Cherem (dart-lang), 2015/03/17 15:03:50]

I had not idea this existed, that's pretty cool!

[kevmoo, 2015/03/17 15:14:39]

:-)

+  popd
+  pub install
+}
+
+clean
+
+dart --checked test/all_tests.dart

[Siggi Cherem (dart-lang), 2015/03/17 15:03:50]

could we call `source test/test.sh` here instead? it runs "all_tests.dart" but
also validates the output of the compiler, runs the analyzer, and checks that
all files are formatted correctly.

[kevmoo, 2015/03/17 15:14:38]

Yes, but let me get this in first.

I was having trouble getting tesh.sh to pass on travis. Wanted to get something
in first.

[Jennifer Messerly, 2015/03/17 15:30:12]

if it helps, we can move the diff'ing of expected output into the Dart test
code.
but test.sh is still nice because it runs the analyzer :)

+
+# Install dart_coveralls; gather and send coverage data.
+if [ "$COVERALLS_TOKEN" ]; then
+  clean
+
+  pub global run dart_coveralls report \
+    --token $COVERALLS_TOKEN \
+    --retry 2 \
+    --exclude-test-files \
+    test/all_tests.dart
+fi