misc: use modern exception syntax

This is fixing for 'legacy exception syntax; use "as" instead of ","'
check-code rule.

check-code has overlooked these, because files aren't recognized as
one to be checked (this problem is fixed by subsequent patch).

contrib/hg-ssh

@@ -52,7 +52,7 b' def main():'
     orig_cmd = os.getenv('SSH_ORIGINAL_COMMAND', '?')
     try:
         cmdargv = shlex.split(orig_cmd)
-    except ValueError, e:
+    except ValueError as e:
         sys.stderr.write('Illegal command "%s": %s\n' % (orig_cmd, e))
         sys.exit(255)
 

contrib/simplemerge

@@ -47,7 +47,7 b' try:'
     opts = {}
     try:
         args = fancyopts.fancyopts(sys.argv[1:], options, opts)
-    except fancyopts.getopt.GetoptError, e:
+    except fancyopts.getopt.GetoptError as e:
         raise ParseError(e)
     if opts['help']:
         showhelp()
@@ -55,11 +55,11 b' try:'
     if len(args) != 3:
             raise ParseError(_('wrong number of arguments'))
     sys.exit(simplemerge.simplemerge(ui.ui(), *args, **opts))
-except ParseError, e:
+except ParseError as e:
     sys.stdout.write("%s: %s\n" % (sys.argv[0], e))
     showhelp()
     sys.exit(1)
-except error.Abort, e:
+except error.Abort as e:
     sys.stderr.write("abort: %s\n" % e)
     sys.exit(255)
 except KeyboardInterrupt:

tests/hghave

@@ -20,7 +20,7 b' def test_features():'
         check, _ = feature
         try:
             check()
-        except Exception, e:
+        except Exception as e:
             print "feature %s failed:  %s" % (name, e)
             failed += 1
     return failed
@@ -45,7 +45,7 b' def _loadaddon():'
     sys.path.insert(0, path)
     try:
         import hghaveaddon
-    except BaseException, inst:
+    except BaseException as inst:
         sys.stderr.write('failed to import hghaveaddon.py from %r: %s\n'
                          % (path, inst))
         sys.exit(2)