Add a global defines.v and rely less on parameters

- This is mainly to avoid "accidents" with default parameter values
diff --git a/verilog/rtl/user_proj_example.v b/verilog/rtl/user_proj_example.v
index d010e77..a72d99e 100644
--- a/verilog/rtl/user_proj_example.v
+++ b/verilog/rtl/user_proj_example.v
@@ -20,8 +20,6 @@
  */
 
 module user_proj_example #(
-    parameter IO_PADS = 38,
-    parameter PWR_PADS = 4,
     parameter BITS = 32
 )(
     inout vdda1,	// User area 1 3.3V supply
@@ -51,16 +49,16 @@
     input  [127:0] la_oen,
 
     // IOs
-    input  [IO_PADS-1:0] io_in,
-    output [IO_PADS-1:0] io_out,
-    output [IO_PADS-1:0] io_oeb
+    input  [`MPRJ_IO_PADS-1:0] io_in,
+    output [`MPRJ_IO_PADS-1:0] io_out,
+    output [`MPRJ_IO_PADS-1:0] io_oeb
 );
     wire clk;
     wire rst;
 
-    wire [IO_PADS-1:0] io_in;
-    wire [IO_PADS-1:0] io_out;
-    wire [IO_PADS-1:0] io_oeb;
+    wire [`MPRJ_IO_PADS-1:0] io_in;
+    wire [`MPRJ_IO_PADS-1:0] io_out;
+    wire [`MPRJ_IO_PADS-1:0] io_oeb;
 
     wire [31:0] rdata; 
     wire [31:0] wdata;
@@ -78,7 +76,7 @@
 
     // IO
     assign io_out = count;
-    assign io_oeb = {(IO_PADS-1){rst}};
+    assign io_oeb = {(`MPRJ_IO_PADS-1){rst}};
 
     // LA
     assign la_data_out = {{(127-BITS){1'b0}}, count};