Issue Description
The sourceJar task outputs files where ${modid}, ${version}, etc are not properly expanded.

Reproduction Steps
Steps to reproduce the behavior:

1. Build the project
2. 7-zip wolfarmor-api-X.X.X-sources.jar
3. Open dev/satyrn/wolfarmor/api/package-info.java
4. @API annotation values are not expanded

Expected Behavior
The source code should have expanded values so the exported files are more useful.

Version Information:

• OS: Windows 10
• Java: jdk1.8.0_261
• Minecraft Version: 1.12.2-14.23.5.2838
• Mod Version: v4.4.3