Revised the prerequisite module declarations in Makefile.PL and Build.PL.

Build.PL

@@ -63,7 +63,7 @@ my $build = Module::Build->new(
     recommends		=> {
         "File::MMagic"			=> 0,
         "IO::Compress::Gzip"	=> 0,
-        "IO::Compress::Bzip2"	=> 2,
+        "IO::Compress::Bzip2"	=> 0,
         "IO::Compress::Xz"		=> 0,
         "Term::ReadKey"			=> 0,
     },

Makefile.PL

@@ -53,7 +53,7 @@ our (%OPT_PREREQ);
 %OPT_PREREQ = (
     "File::MMagic"			=> 0,
     "IO::Compress::Gzip"	=> 0,
-    "IO::Compress::Bzip2"	=> 2,
+    "IO::Compress::Bzip2"	=> 0,
     "IO::Compress::Xz"		=> 0,
     "Term::ReadKey"			=> 0,
 );