make : add train-text-from-scratch (#1850)

* make finetuning example accessible

* fixed: targed was in wrong line

* fixed: name of executable was wrong

* fixed: naming of binary

* fixed: model path was wrong

* fixed clean target

* Update examples/train-text-from-scratch/README.md

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Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

.gitignore

@@ -32,6 +32,7 @@ models/*
 /result
 /perplexity
 /embedding
+/train-text-from-scratch
 /benchmark-matmult
 /vdot
 /Pipfile