changed sourceCompatibility to 1.7
Update class diagram
Added en- and decryption
Added test for en- and decryption
removed new byte[], use byteArrayOut/InputStream
Merge pull request #50 from jan-schreib/build.gradle

changed sourceCompatibility to 1.7
closes #2
Merge pull request #51 from roeslpa/basicSymmetricEncryption

Basic symmetric encryption