adds documentation and some minor improvements

Author: moay

README.md

@@ -1,2 +1,35 @@
+![travis-ci-status](https://travis-ci.org/moay/opensensemap-api-php-client.svg?branch=master)
+
 # opensensemap-api-php-client
+
 A client for retrieving sensor data from a senseBox from the opensensemap api
+
+## Usage
+
+Take a look at the implementation example in the directory `example`.
+
+```php
+$client = \Moay\OpensensemapApiClient\OpensensemapApiClientFactory::create();
+
+// Change senseBox id
+$senseBoxData = $client->getSenseBoxData('someSenseBoxId');
+
+foreach ($senseBoxData->getSensorValues() as $sensorValue) {
+    // $sensorValue->getValueType()
+    // $sensorValue->getValue()
+    // $sensorValue->getUnit()
+    // $sensorValue->getSensorType()
+    // $sensorValue->getMeasurementTime()->format('Y-m-d H:i:s')
+}
+```
+
+## Features
+
+The client gives you the latest data for a specific senseBox from the OpenSenseMap Api.
+
+## License
+
+The client is published under the [MIT license](LICENSE.md).
+
+senseBox and all related contents, visuals and brands are published under CC licenses or other public domain licenses.
+Make sure to check out the project.

composer.json

@@ -3,8 +3,9 @@
     "description": "A client for retrieving sensor data from a senseBox from the opensensemap api",
     "type": "library",
     "require": {
-        "guzzlehttp/guzzle": "^6.3",
-        "ext-json": "*"
+        "php": ">=7.0",
+        "ext-json": "*",
+        "guzzlehttp/guzzle": "^6.3"
     },
     "require-dev": {
         "phpunit/phpunit": "^8.2"