v0.2.0

Complete overhaul
v0.2.0

* AriaProcessor.scala: AriaThread.class, added "--gid=" parameter
* DaemonThread.scala: removed unnecessary items
* "Utils.scala: modified method names to camel case
* AriaProcessor.scala: added restartDownloads()
* DaemonThread.scala: removed all commented code
* DbManager.scala: add isTaskGIDUsed()
* DownloadMonitor.scala: removed commented code
* UpdateProgressJob.scala: all Aria2-related methods have xml-rpc client instance added as parameter
* Utils.scala: generateGID() finished
* XMPPMonitor.scala: modified calling methods to changes