Fix dcompiler.dd formatting, add -dip1000

Add missing comma for 2 SWITCH uses.
Remove unnecessary DD.

Author: ntrel

dcompiler.dd

@@ -523,7 +523,7 @@ $(WINDOWS
         )
       )
 
-      $(SWITCH $(SWNAME -conf)=$(I path)
+      $(SWITCH $(SWNAME -conf)=$(I path),
         use config file at $(I path)
       )
 
@@ -603,6 +603,10 @@ dmd -cov -unittest myprog.d
         implement http://wiki.dlang.org/DIP25 (experimental)
       )
 
+      $(SWITCH $(SWNAME -dip1000),
+        implement $(LINK2 https://github.com/dlang/DIPs/blob/master/DIPs/DIP1000.md, DIP1000) (experimental)
+      )
+
     $(UNIX
       $(SWITCH $(SWNAME -fPIC),
         generate Position Independent Code (which is used
@@ -823,10 +827,10 @@ dmd -cov -unittest myprog.d
       )
 
       $(SWITCH $(SWNAME -od)$(I objdir),
-        $(DD write object files relative to directory $(I objdir)
+        write object files relative to directory $(I objdir)
         instead of to the current directory. $(SWLINK -op)
         can be used if the original package hierarchy should
-        be retained)
+        be retained
       )
       $(SWITCH $(SWNAME -of)$(I filename),
         Set output file name to $(I filename) in the output
@@ -855,7 +859,7 @@ dmd -cov -unittest myprog.d
         done for system and trusted functions, and assertion failures
         are undefined behaviour.
       )
-      $(SWITCH $(SWNAME -run) $(I srcfile args...)
+      $(SWITCH $(SWNAME -run) $(I srcfile args...),
         compile, link, and run the program $(I srcfile) with the
         rest of the
         command line, $(I args...), as the arguments to the program.