Adding a travis job for a minimal build

sys/unix/hints/linux-minimal

@@ -0,0 +1,31 @@
+#
+# NetHack 3.6  linux $NHDT-Date: 1432512814 2018/11/23 16:00:00 $  $NHDT-Branch: master $:$NHDT-Revision: 1.12 $
+# Copyright (c) Patric Mueller
+# NetHack may be freely redistributed.  See license for details. 
+#
+#-PRE
+# Hints file for a minimal build
+# This hints file provides the base for a minimal tty build for Linux
+
+PREFIX=$(wildcard ~)/nethack-minimal
+HACKDIR=$(PREFIX)/games/lib/$(GAME)dir
+SHELLDIR=$(PREFIX)/games
+INSTDIR=$(HACKDIR)
+VARDIR=$(HACKDIR)
+
+CFLAGS=-g -I../include
+
+LINK=$(CC)
+
+WINSRC = $(WINTTYSRC)
+WINOBJ = $(WINTTYOBJ)
+WINLIB = $(WINTTYLIB)
+
+WINTTYLIB=-lcurses
+
+CHOWN=true
+CHGRP=true
+
+VARDIRPERM = 0755
+VARFILEPERM = 0600
+GAMEPERM = 0755