improving docs and configurations

CONTRIBUTING.md

@@ -0,0 +1,10 @@
+Requirements
+------------
+**[wkhtmltopdf](http://wkhtmltopdf.org/) must be installed and working on your system.**
+
+Running tests
+------------
+
+This repo has two kinds of tests: integration and unit test.
+
+Use `mvn test -B` to run only the unit tests.

README.md

@@ -97,6 +97,8 @@ Known issues
 **Output of wkhtmltopdf is being added to resulting pdf** ([Issue #19](https://github.com/jhonnymertz/java-wkhtmltopdf-wrapper/issues/19))
 - Starting from 1.1.10-RELEASE version, there is a method `saveAsDirect(String path)`, which executes wkhtmltopdf passing the `path` as output for wkhtmltopdf, instead of the standard input `-`. This saves the results directly to the specified file `path`.
 
+**Because this library relies on `wkhtmltopdf`, it does not support concurrent PDF generations.**
+
 License
 ------------
 This project is available under MIT Licence.

pom.xml

@@ -39,8 +39,8 @@
     </developers>
 
     <properties>
-        <maven.compiler.source>1.7</maven.compiler.source>
-        <maven.compiler.target>1.7</maven.compiler.target>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>