Set the SASL_PATH variable for the user so that sasl works

The library is hard-coded to look at /usr/lib/sasl2 which we can't
modify on the chromebook;  We have to reply on this env var :-(

packages/mutt.rb

@@ -34,5 +34,6 @@ class Mutt < Package
   def self.install
     system "mkdir -p #{CREW_DEST_DIR}#{CREW_PREFIX}/mail"
     system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+    system "echo 'export SASL_PATH=/usr/local/lib/sasl2' >> ~/.bashrc"
   end
 end