use dontBuild instead of hacks

changes:
 * buildPhase = "true"
 * buildPhase = ":"

pkgs/servers/monitoring/longview/default.nix

@@ -11,15 +11,14 @@ stdenv.mkDerivation rec {
     sha256 = "1i6va44bx2zfgbld7znf1slph0iqidlahq2xh3kd8q4lhvbrjn02";
   };
 
-  patches =
-    [ # log to systemd journal
-      ./log-stdout.patch
-    ];
+  patches = [
+    # log to systemd journal
+    ./log-stdout.patch
+  ];
 
-  postPatch =
-    ''
-      substituteInPlace Linode/Longview/Util.pm --replace /var/run/longview.pid /run/longview.pid
-    '';
+  postPatch = ''
+    substituteInPlace Linode/Longview/Util.pm --replace /var/run/longview.pid /run/longview.pid
+  '';
 
   buildInputs = [ perl makeWrapper glibc ]
     ++ (with perlPackages; [
@@ -37,7 +36,8 @@ stdenv.mkDerivation rec {
       DBDmysql
     ]);
 
-  buildPhase = "true";
+  dontBuild = true;
+
   installPhase = ''
     mkdir -p $out/bin $out/usr
     mv Linode $out

pkgs/servers/rt/default.nix

@@ -7,7 +7,6 @@ stdenv.mkDerivation rec {
 
   src = fetchurl {
     url = "https://download.bestpractical.com/pub/rt/release/${name}.tar.gz";
-
     sha256 = "1hgz50fxv9zdcngww083aqh8vzyk148lm7mcivxflpnsqfw3696x";
   };
 
@@ -15,7 +14,7 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ perl ];
 
-  buildPhase = "true";
+  dontBuild = true;
 
   installPhase = ''
     mkdir $out

pkgs/servers/sql/monetdb/default.nix

@@ -25,15 +25,14 @@ composableDerivation.composableDerivation {} {
     javaSupport = true;
   };
 
-  configurePhase = ":";
-  buildPhase = ":";
-  
+  dontBuild = true;
+
   installPhase = ''
     mkdir $TMP/build
     sh monetdb-install.sh --build=$TMP/build --prefix=$out --enable-sql --enable-xquery
   '';
 
-  meta = { 
+  meta = {
     description = "A open-source database system for high-performance applications in data mining, OLAP, GIS, XML Query, text and multimedia retrieval";
     homepage = http://monetdb.cwi.nl/;
     license = "MonetDB Public License"; # very similar to Mozilla public license (MPL) Version see 1.1 http://monetdb.cwi.nl/Legal/MonetDBLicense-1.1.html 

pkgs/servers/x11/xquartz/default.nix

@@ -98,9 +98,13 @@ let
   };
 in stdenv.mkDerivation {
   name = "xquartz";
+
   buildInputs = [ ruby makeWrapper ];
+
   unpackPhase = "sourceRoot=.";
-  buildPhase = ":";
+
+  dontBuild = true;
+
   installPhase = ''
     cp -rT ${xorg.xinit} $out
     chmod -R u+w $out
@@ -179,6 +183,7 @@ in stdenv.mkDerivation {
       --replace "@DEFAULT_CLIENT@"  "${xterm}/bin/xterm" \
       --replace "@FONTCONFIG_FILE@" "$fontsConfPath"
   '';
+
   meta = with lib; {
     platforms   = platforms.darwin;
     maintainers = with maintainers; [ cstrahan ];