Issue RiotGamesMinions#31 - Lookup the dir hierarchy for .git dir

lib/thor-scmversion/scm_version.rb

@@ -5,12 +5,24 @@ class << self
     #
     # @return [#kind_of? ScmVersion]
     def versioner
-      if(File.exist?  (".git"))
+      if is_git?
         return GitVersion
       else
         return P4Version
       end
     end
+
+    def is_git?
+      file_exists?(Dir.pwd, '.git')
+    end
+
+    def file_exists?(current_dir, file)
+      return true if File.exist?(file)
+      Dir.chdir('..') do
+        return false if Dir.pwd == current_dir
+        file_exists?(current_dir, file)
+      end
+    end
   end
 
   # author Josiah Kiehl <[email protected]>