Replace xcodeenv with new implementation

pkgs/development/mobile/xcodeenv/compose-xcodewrapper.nix

@@ -0,0 +1,29 @@
+{stdenv}:
+{version ? "9.3", xcodeBaseDir ? "/Applications/Xcode.app"}:
+
+assert stdenv.isDarwin;
+
+stdenv.mkDerivation {
+  name = "xcode-wrapper-"+version;
+  buildCommand = ''
+    mkdir -p $out/bin
+    cd $out/bin
+    ln -s /usr/bin/xcode-select
+    ln -s /usr/bin/security
+    ln -s /usr/bin/codesign
+    ln -s /usr/bin/xcrun
+    ln -s /usr/bin/plutil
+    ln -s "${xcodeBaseDir}/Contents/Developer/usr/bin/xcodebuild"
+    ln -s "${xcodeBaseDir}/Contents/Developer/Applications/Simulator.app/Contents/MacOS/Simulator"
+
+    cd ..
+    ln -s "${xcodeBaseDir}/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs"
+
+    # Check if we have the xcodebuild version that we want
+    if [ -z "$($out/bin/xcodebuild -version | grep -x 'Xcode ${version}')" ]
+    then
+        echo "We require xcodebuild version: ${version}"
+        exit 1
+    fi
+  '';
+}