revert embedded templates to use prompt/response

This reverts commit 19753c18c0.

for compat. messages will be added at a later date

template/solar-instruct.gotmpl

@@ -1,16 +1,3 @@
-{{- if .Messages }}
-{{- if .System }}### System:
-{{ .System }}
-
-{{ end }}
-{{- range .Messages }}
-{{- if eq .Role "user" }}### User:
-{{ .Content }}
-{{ else if eq .Role "assistant" }}### Assistant:
-{{ .Content }}</s>
-{{ end }}
-{{ end }}### Assistant:
-{{ else -}}
 {{ if .System }}### System:
 {{ .System }}
 
@@ -20,4 +7,3 @@
 {{ end }}### Assistant:
 {{ .Response }}</s>
 
-{{ end -}}