Exclude .git, spec, and coverage reports from package

There's no need for a packaged admin buildpack to contain all of the
test artifacts, coverage reports, or git repository so exclude them
from the zip when it's created.

.package-exclude

@@ -0,0 +1,4 @@
+.*
+coverage/*
+spec/*
+Rakefile

Rakefile

@@ -93,7 +93,7 @@ task :package, [:zipfile, :hosts] do |t, args|
     system("find #{dest} -type f -exec chmod a+r {} \\;")
     system("find #{dest} -type d -exec chmod a+rx {} \\;")
     system("chmod a+rx #{dest}/bin/*")
-    system("cd #{dest} && zip -r #{zipfile} .")
+    system("cd #{dest} && zip -r #{zipfile} [email protected] .")
   end
 end