Add a script to verify json syntax

This is a useful sanity check to have as we start adding shared
test data.

Author: kytrinyx

.travis.yml

@@ -0,0 +1,11 @@
+language: bash
+
+sudo: false
+
+addons:
+  apt:
+    packages:
+      - jq
+
+script:
+  - bin/jsonlint

README.md

@@ -9,7 +9,7 @@ Please see the [contributing guide](https://github.com/exercism/x-api/blob/maste
 
 ## Test Data Format
 
-Each problem can have a file <problem>.json containing standard test data.
+Each problem can have a file <problem>.json containing standard test data.
 This data can be incoporated into test programs manually or extracted by a
 program.  The file contains a single JSON object with a key for documentation
 and keys for various tests that may be meaningful for a problem.
@@ -24,7 +24,18 @@ Each test uses a key name representative of the test and an object as the
 value.  This object has two keys, "Description" and "Cases".  Description has
 a list of strings as its value.  Cases has a list of objects as its value.
 Each case object represents a separate test case.  A case object should have
-a description field and fields for inputs and outputs.  A test case description should be a short phrase, suitable to be included in an error message.
+a description field and fields for inputs and outputs. A test case description
+should be a short phrase, suitable to be included in an error message.
+
+## Automated Tests
+
+The only thing that we're testing at the moment, is whether or not shared test data
+is valid json.
+
+If you want to run this before you commit, you will need to install
+[jq](https://stedolan.github.io/jq/download/). Then run the script with:
+
+    bin/jsonlint
 
 ## License
 

bin/jsonlint

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+STATUS=0
+for f in $(ls *.json); do
+	cat $f | jq . > /dev/null 2>&1
+	if [ $? != 0 ]; then
+		echo "Invalid json: $f"
+		STATUS=1
+	fi
+done
+exit $STATUS