Merge pull request #4 from MtotheKay/master

Readme update to include hint to jdk

Author: fquirin

README.md

@@ -13,7 +13,7 @@ To use the interface make sure the server has SDK support enabled (via admin-too
 - Import the maven project into the IDE of your choice (tested with Eclipse).
 - Create a package for your developer account ID under 'net.b07z.sepia.sdk.services' (e.g. "uid1010" -> net.b07z.sepia.sdk.services.uid1010).
 - Open 'Settings/sdk.properties' and put in your credentials (ID + password of your SEPIA account with 'developer' role) and the endpoint URL of your SEPIA-Assist server.
-- Modify and run the various '[.main.Test***.java](https://github.com/SEPIA-Framework/sepia-sdk-java/tree/dev/src/main/java/net/b07z/sepia/sdk/main)' classes to test the upload of one of the demo services. Check the result for errors.
+- Modify and run the various '[.main.Test***.java](https://github.com/SEPIA-Framework/sepia-sdk-java/tree/dev/src/main/java/net/b07z/sepia/sdk/main)' classes to test the upload of one of the demo services. Check the result for errors. Make sure you installed a jdk on the S.E.P.I.A. server (e.g.: sudo apt install openjdk-8-jdk)
 - Check-out the examples under '[.services.uid1007.*](https://github.com/SEPIA-Framework/sepia-sdk-java/tree/dev/src/main/java/net/b07z/sepia/sdk/services/uid1007)' to get an idea of how a SDK custom service works (until a real documentation is ready ^^).
 - Open your SEPIA client, login with the same user ID you used for development and make a real test of your custom service.