README and Makefile cleanup

Makefile

@@ -1,15 +1,6 @@
-.PHONY: all clean abnf_patch test
+.PHONY: all abnf_patch
 
-all: dhall/_grammar.py
-
-clean:
-	rm -rf dhall/_grammar.py dhall.abnf
-
-dhall/_grammar.py: dhall.abnf abnf2bnf.py bnf2parglare.py json2python.py grammar_desugaring.py
-	cat $< | python abnf2bnf.py complete-expression | python bnf2parglare.py | python json2python.py grammar > $@
-
-dhall.abnf: dhall-lang/standard/dhall.abnf dhall.abnf.patch
-	patch --binary -o $@ $^
+all:
 
 abnf_patch:
-	diff -u dhall-lang/standard/dhall.abnf dhall.abnf > dhall.abnf.patch
+	diff -u dhall-lang/standard/dhall.abnf dhall.abnf > dhall.abnf.patch; test $$? -le 1

README.md

@@ -4,12 +4,19 @@ Dhall for python
 [![Build Status](https://travis-ci.com/SupraSummus/dhall-python.svg?branch=master)](https://travis-ci.com/SupraSummus/dhall-python)
 [![codecov](https://codecov.io/gh/SupraSummus/dhall-python/branch/master/graph/badge.svg)](https://codecov.io/gh/SupraSummus/dhall-python)
 
-Pure python implementation of dhall language.
+Pure python implementation of [dhall](https://github.com/dhall-lang/dhall-lang) language.
 
 **Work in progres**
 
-    make test
+    python setup.py build  # to patch the grammar and compile parser tables
+    python setup.py test  # to run tests
+    flake8  # to lint the code
+    make abnf_patch  # to make changes to dhall.abnf persistent
 
+Details:
+ * parsing is done using [parglare](https://github.com/igordejanovic/parglare) GLR parser library
+ * acceptance tests comes from dhall-lang repository
+ * parser tests comes form dhall-haskell repository
 
 abnf2bnf.py
 -----------