Clean up pg_regress --help output

Put options listing in a less random order, fix capitalization, and
some typos.

src/test/regress/pg_regress.c

@@ -1870,40 +1870,40 @@ help(void)
 {
 	printf(_("PostgreSQL regression test driver\n"));
 	printf(_("\n"));
-	printf(_("Usage: %s [options...] [extra tests...]\n"), progname);
+	printf(_("Usage:\n  %s [OPTION]... [EXTRA-TEST]...\n"), progname);
 	printf(_("\n"));
 	printf(_("Options:\n"));
+	printf(_("  --create-role=ROLE        create the specified role before testing\n"));
 	printf(_("  --dbname=DB               use database DB (default \"regression\")\n"));
 	printf(_("  --debug                   turn on debug mode in programs that are run\n"));
+	printf(_("  --dlpath=DIR              look for dynamic libraries in DIR\n"));
+	printf(_("  --encoding=ENCODING       use ENCODING as the encoding\n"));
 	printf(_("  --inputdir=DIR            take input files from DIR (default \".\")\n"));
-	printf(_("  --load-language=lang      load the named language before running the\n"));
+	printf(_("  --launcher=CMD            use CMD as launcher of psql\n"));
+	printf(_("  --load-extension=EXT      load the named extension before running the\n"));
 	printf(_("                            tests; can appear multiple times\n"));
-	printf(_("  --load-extension=ext      load the named extension before running the\n"));
+	printf(_("  --load-language=LANG      load the named language before running the\n"));
 	printf(_("                            tests; can appear multiple times\n"));
-	printf(_("  --create-role=ROLE        create the specified role before testing\n"));
 	printf(_("  --max-connections=N       maximum number of concurrent connections\n"));
-	printf(_("                            (default is 0 meaning unlimited)\n"));
-	printf(_("  --encoding=ENCODING       use ENCODING as the encoding\n"));
+	printf(_("                            (default is 0, meaning unlimited)\n"));
 	printf(_("  --outputdir=DIR           place output files in DIR (default \".\")\n"));
 	printf(_("  --schedule=FILE           use test ordering schedule from FILE\n"));
 	printf(_("                            (can be used multiple times to concatenate)\n"));
-	printf(_("  --dlpath=DIR              look for dynamic libraries in DIR\n"));
 	printf(_("  --temp-install=DIR        create a temporary installation in DIR\n"));
 	printf(_("  --use-existing            use an existing installation\n"));
-	printf(_("  --launcher=CMD            use CMD as launcher of psql\n"));
 	printf(_("\n"));
 	printf(_("Options for \"temp-install\" mode:\n"));
+	printf(_("  --extra-install=DIR       additional directory to install (e.g., contrib)\n"));
 	printf(_("  --no-locale               use C locale\n"));
-	printf(_("  --top-builddir=DIR        (relative) path to top level build directory\n"));
 	printf(_("  --port=PORT               start postmaster on PORT\n"));
-	printf(_("  --temp-config=PATH        append contents of PATH to temporary config\n"));
-	printf(_("  --extra-install=DIR       additional directory to install (e.g., contrib\n"));
+	printf(_("  --temp-config=FILE        append contents of FILE to temporary config\n"));
+	printf(_("  --top-builddir=DIR        (relative) path to top level build directory\n"));
 	printf(_("\n"));
 	printf(_("Options for using an existing installation:\n"));
 	printf(_("  --host=HOST               use postmaster running on HOST\n"));
 	printf(_("  --port=PORT               use postmaster running at PORT\n"));
 	printf(_("  --user=USER               connect as USER\n"));
-	printf(_("  --psqldir=DIR             use psql in DIR (default: find in PATH)\n"));
+	printf(_("  --psqldir=DIR             use psql in DIR (default: configured bindir)\n"));
 	printf(_("\n"));
 	printf(_("The exit status is 0 if all tests passed, 1 if some tests failed, and 2\n"));
 	printf(_("if the tests could not be run for some reason.\n"));