Reorganize D modules a bit

Rsconscript

@@ -72,7 +72,7 @@ end
 hulk_env = env "hulk", use: %w[ldc2 x86_64-elf-gcc] do |env|
   env["sources"] = glob("src/hulk/**/*.d")
   env["DFLAGS"] += %w[-mtriple=x86_64-unknown-elf --betterC -release -O3 --wi --enable-cross-module-inlining]
-  env["D_IMPORT_PATH"] += %w[src/hulk src/common]
+  env["D_IMPORT_PATH"] += %w[src]
   env["LD"] = "x86_64-elf-gcc"
   env["LDFLAGS"] += %w[-nostdlib -Tsrc/hulk/hulk.ld -Wl,-Map,${_TARGET}.map]
   env["LDCMD"] = %w[${LD} -o ${_TARGET} ${LDFLAGS} ${_SOURCES} ${LIBDIRPREFIX}${LIBPATH} ${LIBLINKPREFIX}${LIBS}]
@@ -98,7 +98,7 @@ hello_env = env "hello", use: %w[ldc2 x86_64-w64-mingw32-gcc] do |env|
   env.depends("^/hulk_bin.o", hulk_env.expand("^/hulk.bin"))
   env["sources"] << "^/hulk_bin.o"
   env["DFLAGS"] += %w[-mtriple=x86_64-unknown-windows-coff --betterC -release -O3 --wi --enable-cross-module-inlining]
-  env["D_IMPORT_PATH"] += %w[src/hello src/hulk uefi-d/source src/common]
+  env["D_IMPORT_PATH"] += %w[src uefi-d/source]
   env["LD"] = "x86_64-w64-mingw32-gcc"
   env["LDFLAGS"] += %w[-nostdlib -Wl,-dll -shared -Wl,--subsystem,10 -e efi_main -Wl,-Map,${_TARGET}.map]
   env["LDCMD"] = %w[${LD} -o ${_TARGET} ${LDFLAGS} ${_SOURCES} ${LIBDIRPREFIX}${LIBPATH} ${LIBLINKPREFIX}${LIBS}]

src/hello/hello.d

@@ -1,6 +1,8 @@
+module hello.hello;
+
 import uefi;
-import output;
-import scratch;
+import hello.output;
+import hello.scratch;
 import hulk.bootinfo;
 import hos.page_table;
 import hos.cpu;

src/hello/output.d

@@ -1,5 +1,7 @@
+module hello.output;
+
 import uefi;
-import hello;
+import hello.hello;
 import core.stdc.stdarg;
 
 private size_t format_hex(CHAR16 * s, ulong v, bool ptr)

src/hello/scratch.d

@@ -1,3 +1,5 @@
+module hello.scratch;
+
 align(4096) __gshared ubyte[1024 * 1024] scratch;
 __gshared size_t scratch_used;
 

src/hulk/bootinfo.d

@@ -1,3 +1,5 @@
+module hulk.bootinfo;
+
 struct BootInfo
 {
     struct MemoryRegion

src/hulk/hulk.d

@@ -1,3 +1,5 @@
+module hulk.hulk;
+
 import hulk.bootinfo;
 import hos.memory;
 import ldc.attributes;