Alpha release of java support

Here are the steps to test.

1. Make sure java and vscode are installed on system.
2. Install the java extension pack into vscode.
   https://marketplace.visualstudio.com/items?itemName=vscjava.vscode-java-pack
3. Install the 2 .VSIX files attached to this repo. To do this, open vscode, open the command palette (ctrl + shift + p), search for install from vsix. Install both, ignore the first ones request to reload the window. perform the reload for the second one.
4. After a restart, go into the command palette, and search for wpilib: create new project from template. select that. If it asks for a language (it shouldn't), select java, then select a template. It will ask for a folder. Create a new empty folder somewhere on disk, and go into that folder and select it. It will ask to open the new project.
5. Once project is open, give it a few seconds for the java extension to load. You'll see on the bottom left what looks like gradle tasks. Wait for those tasks to stop.
6. To deploy, hit F5. To debug, go into the debugging panel on the left, switch the debug configuration to WPILib Debug. This will switch F5 to debug. Switch it back to go back to deploying. Deploy can also happen with either the Deploy Robot Code command in the command palette, or if you click on the ... at the top right of the editor, there will be a Deploy Robot Code button.
7. ???
8. Profit

If you already have an existing project, Follow the first 3 steps above, then the ones below.

1. Open your gradlerio project in vscode.
2. Go into the command palette, and search for WPILib: Set Language. Select java.
3. Go into the debug configuration pane, click on the selection at the top for configurations, and select Add configurations. Select WPILib debug and deploy. Now the project will be just like the templated one. Go back to step 6 of the fresh project instructions.