Rename hydra_*.pl to hydra-*

The underscores are ugly and the .pl extension is an implementation
detail that shouldn't be visible to the outside.

Also, get rid of the *.in files.  It's not really necessary to
generate them.  And I was always modifying the wrong file.

src/script/Makefile.am

@@ -1,19 +1,19 @@
 EXTRA_DIST = \
-  hydra_control.sh \
-  nix-prefetch-svn \
-  nix-prefetch-git \
-  nix-prefetch-bzr \
-  nix-prefetch-hg 
-
-bin_SCRIPTS = \
-  hydra_build.pl \
-  hydra_evaluator.pl \
-  hydra_queue_runner.pl \
-  hydra_server.pl \
-  hydra_update_gc_roots.pl \
-  hydra_create.pl \
+  hydra-control \
   nix-prefetch-svn \
   nix-prefetch-git \
   nix-prefetch-bzr \
   nix-prefetch-hg \
-  hydra_control.sh
+  $(bin_SCRIPTS)
+
+bin_SCRIPTS = \
+  hydra-build \
+  hydra-evaluator \
+  hydra-queue-runner \
+  hydra-server \
+  hydra-update-gc-roots \
+  hydra-create \
+  nix-prefetch-svn \
+  nix-prefetch-git \
+  nix-prefetch-bzr \
+  nix-prefetch-hg

src/script/hydra-build

@@ -1,4 +1,4 @@
-#! @perl@ -w -I@nix@/libexec/nix
+#! /var/run/current-system/sw/bin/perl -w
 
 use strict;
 use File::Basename;
@@ -430,7 +430,7 @@ sub doBuild {
 }
 
 
-my $buildId = $ARGV[0] or die;
+my $buildId = $ARGV[0] or die "syntax: $0 BUILD-ID\n";
 print STDERR "performing build $buildId\n";
 
 if ($ENV{'HYDRA_MAIL_TEST'}) {

src/script/hydra-evaluator

@@ -1,4 +1,4 @@
-#! @perl@ -w -I@nix@/libexec/nix
+#! /var/run/current-system/sw/bin/perl -w
 
 use strict;
 use feature 'switch';

src/script/hydra-queue-runner

@@ -1,4 +1,4 @@
-#! @perl@ -w -I@nix@/libexec/nix
+#! /var/run/current-system/sw/bin/perl -w
 
 use strict;
 use Cwd;
@@ -138,7 +138,7 @@ sub checkBuilds {
                     open LOG, ">$logfile" or die "cannot create logfile $logfile";
                     POSIX::dup2(fileno(LOG), 1) or die;
                     POSIX::dup2(fileno(LOG), 2) or die;
-                    exec("hydra_build.pl", $id);
+                    exec("hydra-build", $id);
                 };
                 warn "cannot start build $id: $@";
                 POSIX::_exit(1);

src/script/hydra-server

@@ -1,4 +1,4 @@
-#! @perl@ -w -I@nix@/libexec/nix
+#! /var/run/current-system/sw/bin/perl -w
 
 BEGIN {
     $ENV{CATALYST_SCRIPT_GEN} = 40;

src/script/hydra-update-gc-roots

@@ -1,4 +1,4 @@
-#! @perl@ -w -I@nix@/libexec/nix
+#! /var/run/current-system/sw/bin/perl -w
 
 use strict;
 use File::Path;