(GH-1292) Ensure manifest extracted on unpackself

If the `choco.exe.manifest` file is not present on first use of
choco.exe, it extracts the file. However Windows will have already
cached that choco.exe doesn't have a manifest and will not recheck
until the choco.exe changes (last modified time) as it caches that it
doesn't have a manifest. To force a recheck, someone would need to
"touch" the file to change the last modified date.

The issue comes down to the fact that a manifest file needs to be in
place when choco is installed, before the first time that `choco.exe`
gets called. Ensure that the manifest file is packaged up and it will
be unpacked automatically next to choco at the right time.

.build.custom/nugetPrepare.post.step

@@ -39,6 +39,7 @@
     <exec program="${app.choco}"
           workingdir="${dirs.drop.nuget}${path.separator}chocolatey${path.separator}tools${path.separator}chocolateyInstall"
           commandline="${args.choco}" if="${platform::is-windows()}" />
+    <delete file="${dirs.drop.nuget}${path.separator}chocolatey${path.separator}tools${path.separator}chocolateyInstall${path.separator}tools${path.separator}detector.zip" failonerror="false" />
   </target>
 
   <target name="copy_legal">

src/chocolatey/infrastructure.app/commands/ChocolateyUnpackSelfCommand.cs

@@ -86,7 +86,11 @@ public virtual void noop(ChocolateyConfiguration configuration)
         public virtual void run(ChocolateyConfiguration configuration)
         {
             this.Log().Info("{0} is unpacking required files for use. Overwriting? {1}".format_with(ApplicationParameters.Name, configuration.Force));
-            //refactor - thank goodness this is temporary, cuz manifest resource streams are dumb
+            // refactor - thank goodness this is temporary, cuz manifest resource streams are dumb
+
+            // unpack the manifest file as well
+            AssemblyFileExtractor.extract_all_resources_to_relative_directory(_fileSystem, Assembly.GetAssembly(typeof(ChocolateyUnpackSelfCommand)), _fileSystem.get_directory_name(_fileSystem.get_current_assembly_path()), new List<string>(), "chocolatey.console");
+
             IList<string> folders = new List<string>
                 {
                     "helpers",