Adds ghost visible countdowns for bombs

🆑 coiax
rscadd: For extra observer drama, ghosts can now visibly see the
countdown of various explosives.
/🆑

- Also updates my build script to take account of the move of dm.sh

tools/linux_build.py

@@ -31,7 +31,7 @@ def stage2(map):
         txt = "-M{}".format(map)
     else:
         txt = ''
-    args = "bash dm.sh {} tgstation.dme".format(txt)
+    args = "bash tools/travis/dm.sh {} tgstation.dme".format(txt)
     print(args)
     p = subprocess.Popen(args, shell=True)
     wait(p)