New Launcher Release

[resech]

Picking up on the testing request in #27 (comment), I built a version of the launcher based off commit 5879090 and tested these scenarios:

Updating the launcher from the current release version of Xmage (xmage_1.4.57V2) on Windows:

• XMageLauncher-0.3.8.jar was removed
• XMageLauncher-0.4.0.jar was downloaded
• Automatic relaunch worked but run-Launcher.cmd and run-launcher-and-wait.cmd still pointed to the old 0.3.8 version so a further manual launch using those files fails.
• Launcher version in installed.properties was not updated.
• Manual launch from the command line using the updated filename works and the window shows the version has been updated so I'm not prompted to update again (I guess this means the line in installed.properties isn't the only check or isn't checked?)

Updating the launcher from a build based off commit 9496bb5 (which contains lots of .de references) on Windows:

• Same as release version testing above, new version of the launcher was downloaded and old version was removed.
• Automatic relaunch succeeded.
• Any launcher files were not updated, installed.properties was also not updated.
• Manual launch with the new file named worked and did not prompt for re-download of the launcher.

I tested both of these cases in Linux as well, only using java -jar to launch the Launcher files, I got the same result as the Windows testing above:

• Download and removal of old version worked
• Automatic relaunched worked
• installed.properties was not updated
• Manual launch did not prompt for a re-download of the launcher.

One other note, the Use XMage/System Java selection does not appear to be saved. If you do not install XMage java you are prompted at every button press to reconfirm you want to use System Java or Install XMage java. Not sure if this is intentional or not. That said, I was still able to download the rest of the XMage files and install them using system java (1.8.0_452 in my case).

Just for documentation, the config file I used was https://resech.github.io/xmage/config.json, it's the same as xmage.today just with updated launcher settings.

[JayDi85]

Thanks for tests, I’ll add run-scripts update too. Also I fixed system/xmage java confirmation in last commits — it must ask about system usage on fail update only. Maybe something miss.

The final goal: distribute launcher with xmage files without java and it must work from the box with any xmage version. Use cases: user open release history, download old xmage version, unpack and play with it without any upgrades - only java must be downloaded. Current master version fail such manual test.