Bump loofah from 2.0.3 to 2.3.1 in /play-with-docker/Portus

Bumps [loofah](https://github.com/flavorjones/loofah) from 2.0.3 to 2.3.1.
- [Release notes](https://github.com/flavorjones/loofah/releases)
- [Changelog](https://github.com/flavorjones/loofah/blob/master/CHANGELOG.md)
- [Commits](flavorjones/loofah@v2.0.3...v2.3.1)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

play-with-docker/Portus/Gemfile.lock

@@ -85,6 +85,7 @@ GEM
     columnize (0.9.0)
     crack (0.4.3)
       safe_yaml (~> 1.0.0)
+    crass (1.0.5)
     crono (0.9.0)
       activerecord (~> 4.0)
       activesupport (~> 4.0)
@@ -166,7 +167,8 @@ GEM
     listen (3.0.6)
       rb-fsevent (>= 0.9.3)
       rb-inotify (>= 0.9.7)
-    loofah (2.0.3)
+    loofah (2.3.1)
+      crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     lumberjack (1.0.10)
     mail (2.6.4)
@@ -179,15 +181,15 @@ GEM
     mime-types (3.0)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2016.0221)
-    mini_portile2 (2.0.0)
+    mini_portile2 (2.1.0)
     minitest (5.8.4)
     multi_json (1.11.2)
     multipart-post (2.0.0)
     mysql2 (0.3.18)
     nenv (0.3.0)
     net-ldap (0.11)
-    nokogiri (1.6.7.2)
-      mini_portile2 (~> 2.0.0.rc2)
+    nokogiri (1.6.8.1)
+      mini_portile2 (~> 2.1.0)
     notiffany (0.0.8)
       nenv (~> 0.1)
       shellany (~> 0.0)