setup.py: make warning and error messages easier to recognize

setup.py

@@ -69,18 +69,21 @@ else:
 
 distr_root = os.path.dirname(os.path.abspath(__file__))
 
-def header(title=''):
-    return title.center(79, '*')
+def banner(title=''):
+    starred = title.center(79, '*')
+    return '\n' + starred if title else starred
 
-error_msg = """{sep}
+error_msg = """{header}
 The compilation of Kwant has failed.  Please examine the error message
 above and consult the installation instructions in README.rst.
 You might have to customize {{file}}.
-{sep}
+
 Build configuration was:
+
 {{summary}}
-{sep}"""
-error_msg = error_msg.format(sep=header())
+{sep}
+"""
+error_msg = error_msg.format(header=banner(' Error '), sep=banner())
 
 class kwant_build_ext(build_ext):
     def run(self):
@@ -98,8 +101,9 @@ class kwant_build_ext(build_ext):
             print(error_msg.format(file=CONFIG_FILE, summary=build_summary),
                   file=sys.stderr)
             raise
-        print(header(' Build summary '))
+        print(banner(' Build summary '))
         print(build_summary)
+        print(banner())
 
 
 class build_tut(Command):
@@ -151,7 +155,7 @@ class test(Command):
         self.run_command('build')
         major, minor = sys.version_info[:2]
         lib_dir = "build/lib.{0}-{1}.{2}".format(get_platform(), major, minor)
-        print(header(' Tests '))
+        print()
         if not run(argv=[__file__, '-v', lib_dir]):
             raise DistutilsError('at least one of the tests failed')
 
@@ -188,7 +192,7 @@ class kwant_sdist(distutils_sdist):
                 with open(distr_root + '/MANIFEST', 'r') as f:
                     line = f.read()
             except IOError:
-                print("error: MANIFEST file is missing and Git is not"
+                print("Error: MANIFEST file is missing and Git is not"
                       " available to regenerate it.", file=sys.stderr)
                 exit(1)
             trustworthy = not line.strip().startswith('#')
@@ -209,15 +213,17 @@ class kwant_sdist(distutils_sdist):
         distutils_sdist.run(self)
 
         if names is None:
-            print(header(' Warning '),
+            print(banner(' Warning '),
 """Git was not available for re-generating the MANIFEST file (the list of file
 names to be included in the source distribution).  The old MANIFEST was used.""",
+                  banner(),
                   sep='\n', file=sys.stderr)
 
         if not trustworthy:
-            print(header(' Warning '),
+            print(banner(' Warning '),
 """The existing MANIFEST file seems to have been generated by distutils (it begins
 with a comment).  It may well be incomplete.""",
+                  banner(),
                   sep='\n', file=sys.stderr)
 
 # Other than the "if not use_git" clause in the beginning, this is an exact copy