revamp of library builds

- remove cross compiler stuff
- make use of Install.py consistent
- provide options for Makefile.serial and Makefile.mpi that match those in src

lib/Install.py

@@ -70,23 +70,31 @@ if not os.path.exists("Makefile.%s" % machine):
 lines = open("Makefile.%s" % machine,'r').readlines()
 fp = open("Makefile.auto",'w')
 
+has_extramake = False
 for line in lines:
   words = line.split()
-  if len(words) == 3 and extraflag and \
-        words[0] == "EXTRAMAKE" and words[1] == '=':
-    line = line.replace(words[2],"Makefile.lammps.%s" % suffix)
-  print >>fp,line,
+  if len(words) == 3 and words[0] == "EXTRAMAKE" and words[1] == '=':
+    has_extramake = True
+    if extraflag:
+      line = line.replace(words[2],"Makefile.lammps.%s" % suffix)
+  fp.write(line)
 
 fp.close()
 
-# make the library via Makefile.auto
+# make the library via Makefile.auto optionally with parallel make
+
+try:
+  import multiprocessing
+  n_cpus = multiprocessing.cpu_count()
+except:
+  n_cpus = 1
 
 print("Building lib%s.a ..." % lib)
-cmd = "make -f Makefile.auto clean; make -f Makefile.auto"
+cmd = "make -f Makefile.auto clean; make -f Makefile.auto -j%d" % n_cpus
 txt = subprocess.check_output(cmd,shell=True,stderr=subprocess.STDOUT)
-print(txt)
+print(txt.decode('UTF-8'))
 
 if os.path.exists("lib%s.a" % lib): print("Build was successful")
 else: error("Build of lib/%s/lib%s.a was NOT successful" % (lib,lib))
-if not os.path.exists("Makefile.lammps"):
+if has_extramake and not os.path.exists("Makefile.lammps"):
   print("lib/%s/Makefile.lammps was NOT created" % lib)