big update

- remove not supported anymore procedural syntax for main functions
- use App instead of main
- auto format
- move comments to have more user-friendly access to "run" and "debug"
  button for Apps
- move generators to dedicated new file

src/main/scala/mylib/MyTopLevelGen.scala

@@ -0,0 +1,25 @@
+package mylib
+
+import spinal.core._
+
+object MyTopLevelVerilog extends App {
+  // Generate the MyTopLevel's Verilog
+  SpinalVerilog(new MyTopLevel)
+}
+
+object MyTopLevelVhdl extends App {
+  // Generate the MyTopLevel's VHDL
+  SpinalVhdl(new MyTopLevel)
+}
+
+// Custom SpinalHDL configuration with synchronous reset instead of the default asynchronous one
+// This configuration can be resued everywhere
+object MySpinalConfig
+    extends SpinalConfig(
+      defaultConfigForClockDomains = ClockDomainConfig(resetKind = SYNC)
+    )
+
+object MyTopLevelVerilogWithCustomConfig extends App {
+  // Generate the MyTopLevel's Verilog using the above custom configuration.
+  MySpinalConfig.generateVerilog(new MyTopLevel)
+}