font-awesome: make font-awesome_5 the defautl

It is confusing that font-awesome_4 is the font,
one get when installing font-awesome-ttf.
I don't really see a use case to keep the old version around.

pkgs/data/fonts/font-awesome-4/default.nix

@@ -1,28 +0,0 @@
-{ stdenv, fetchzip }:
-
-let
-  version = "4.7.0";
-in fetchzip rec {
-  name = "font-awesome-${version}";
-
-  url = "https://github.com/FortAwesome/Font-Awesome/archive/v${version}.zip";
-
-  postFetch = ''
-    mkdir -p $out/share/fonts
-    unzip -j $downloadedFile Font-Awesome-${version}/fonts/fontawesome-webfont.ttf -d $out/share/fonts/truetype
-  '';
-
-  sha256 = "0w8y7gxbqiy444phg4jl89kc5hq3jffbkhab8p110qy9jx8s106s";
-
-  meta = with stdenv.lib; {
-    description = "Font Awesome - TTF font";
-    longDescription = ''
-      Font Awesome gives you scalable vector icons that can instantly be customized.
-      This package includes only the TTF font. For full CSS etc. see the project website.
-    '';
-    homepage = http://fortawesome.github.io/Font-Awesome/;
-    license = licenses.ofl;
-    platforms = platforms.all;
-    maintainers = with maintainers; [ abaldeau ];
-  };
-}

pkgs/top-level/aliases.nix

@@ -99,7 +99,7 @@ mapAliases ({
   firefox-wrapper = firefox;          # 2016-01
   firefoxWrapper = firefox;           # 2015-09
   flameGraph = flamegraph; # added 2018-04-25
-  font-awesome-ttf = font-awesome_4; # 2018-02-25
+  font-awesome-ttf = font-awesome; # 2018-02-25
   foomatic_filters = foomatic-filters;  # 2016-08
   fuse_exfat = exfat;                   # 2015-09-11
   fuseki = apache-jena-fuseki; # added 2018-04-25

pkgs/top-level/all-packages.nix

@@ -15560,8 +15560,8 @@ in
 
   fira-mono = callPackage ../data/fonts/fira-mono { };
 
-  font-awesome_4 = callPackage ../data/fonts/font-awesome-4 { };
   font-awesome_5 = callPackage ../data/fonts/font-awesome-5 { };
+  font-awesome = font-awesome_5;
 
   freefont_ttf = callPackage ../data/fonts/freefont-ttf { };
 
@@ -21506,7 +21506,7 @@ in
 
   bftools = callPackage ../applications/science/biology/bftools { };
 
-  cmtk = callPackage ../applications/science/biology/cmtk { }; 
+  cmtk = callPackage ../applications/science/biology/cmtk { };
 
   conglomerate = callPackage ../applications/science/biology/conglomerate { };