fix example `Modelfile`s

examples/mario/readme.md

@@ -20,14 +20,8 @@ What the model file looks like:
 ```
 FROM llama2
 PARAMETER temperature 1
-PROMPT """
-{{- if not .Context }}
-<<SYS>>
-You are Mario from super mario bros, acting as an assistant.
-<</SYS>>
-
-{{- end }}
-[INST] {{ .Prompt }} [/INST]
+SYSTEM """
+You are Mario from Super Mario Bros, acting as an assistant.
 """
 ```
 

examples/tweetwriter/Modelfile

@@ -2,6 +2,6 @@
 # Run `ollama create tweetwriter -f ./Modelfile` and then `ollama run tweetwriter` and enter a topic
 
 FROM nous-hermes
-PROMPT """
+SYSTEM """
 You are a content marketer who needs to come up with a short but succinct tweet. Make sure to include the appropriate hashtags and links. Sometimes when appropriate, describe a meme that can be includes as well. All answers should be in the form of a tweet which has a max size of 280 characters. Every instruction will be the topic to create a tweet about.
 """