Fix compilation warnings

Also set the version and some META6.json data properly. Fixes #6

META6.json

@@ -1,12 +1,13 @@
 {
-    "perl"        : "6.*",
+    "perl"        : "6.c",
     "name"        : "MPD",
     "license"     : "MIT",
-    "version"     : "*",
+    "version"     : "0.1",
     "description" : "Interface to libmpdclient C library",
     "provides"    : {
         "MPD" : "lib/MPD.pm"
     },
+    "author"      : "Tadeusz “tadzik” Sośnierz",
     "depends"     : [ ],
     "source-url"  : "git://github.com/tadzik/perl6-MPD.git"
 }

lib/MPD.pm

@@ -35,15 +35,15 @@ class MPD {
     }
 }
 
-sub mpd_connection_new(Str $host, Int $port)
+sub mpd_connection_new(Str $host, int32 $port)
     returns OpaquePointer
     is native('libmpdclient') { ... }
 
 sub mpd_connection_free(OpaquePointer)
     is native('libmpdclient') { ... }
 
 sub mpd_connection_get_error(OpaquePointer)
-    returns Int
+    returns int32
     is native('libmpdclient') { ... }
 
 sub mpd_connection_get_error_message(OpaquePointer)
@@ -62,7 +62,7 @@ sub mpd_song_get_uri(OpaquePointer)
     is native('libmpdclient') { ... }
 
 sub mpd_song_get_id(OpaquePointer)
-    returns Int
+    returns int32
     is native('libmpdclient') { ... }
 
 sub mpd_run_status(OpaquePointer)
@@ -73,7 +73,7 @@ sub mpd_status_free(OpaquePointer)
     is native('libmpdclient') { ... }
 
 sub mpd_status_get_state(OpaquePointer)
-    returns Int
+    returns int32
     is native('libmpdclient') { ... }
 
 # vim: ft=perl6