changed sourceCompatibility to 1.7
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
Added hybrid encryption and decryption method to CryptoUtils (encryptMessage and decryptMessage)
Merge pull request #52 from L-Henke/hybridEnc

Added hybrid encryption and decryption method to CryptoUtils
combined symm dec and enc test