Make the web app select the language based on browser values

Language also can be selected using the `?l=langcode` query string.

app/translations/hu/LC_MESSAGES/messages.po

@@ -0,0 +1,61 @@
+# Hungarian translations for PROJECT.
+# Copyright (C) 2018 ORGANIZATION
+# This file is distributed under the same license as the PROJECT project.
+# FIRST AUTHOR <EMAIL@ADDRESS>, 2018.
+#
+msgid ""
+msgstr ""
+"Project-Id-Version: 0.1\n"
+"Report-Msgid-Bugs-To: gergely@polonkai.eu\n"
+"POT-Creation-Date: 2018-06-29 14:14+0200\n"
+"PO-Revision-Date: 2018-06-29 14:26+0200\n"
+"Last-Translator: Gergely Polonkai <gergely@polonkai.eu>\n"
+"Language: hu\n"
+"Language-Team: hu <gergely@polonkai.eu>\n"
+"Plural-Forms: nplurals=1; plural=0\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=utf-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Generated-By: Babel 2.6.0\n"
+
+#: app/forms.py:8
+msgid "Username"
+msgstr "Felhasználónév"
+
+#: app/forms.py:9
+msgid "Email address"
+msgstr "E-mail cím"
+
+#: app/forms.py:10
+msgid "Password"
+msgstr "Jelszó"
+
+#: app/forms.py:11
+msgid "Password, once more"
+msgstr "Jelszó még egszer"
+
+#: app/forms.py:15
+msgid "The two passwords must match!"
+msgstr "A két jelszónak egyeznie kell!"
+
+#: app/templates/base.html:21
+#, python-format
+msgid "Logged in as %(username)s"
+msgstr "Bejelentkezve %(username)s néven"
+
+#: app/templates/base.html:25
+msgid "Login"
+msgstr "Bejelentkezés"
+
+#: app/templates/base.html:27
+msgid "Logout"
+msgstr "Kijelentkezés"
+
+#: app/templates/index.html:4
+#, python-format
+msgid "Welcome to Calendar.social, %(username)s!"
+msgstr "Üdv a Calendar.social-ben, %(username)s!"
+
+#: app/templates/registration.html:27
+msgid "Register"
+msgstr "Regisztráció"