add gitattribute to force LF line endings and set cleanyaml.py to read/write as utf8 always

.gitattributes

@@ -0,0 +1,9 @@
+*.yaml text eol=lf
+*.py text eol=lf
+*.md text eol=lf
+*.sql text eol=lf
+*.bat text eol=lf
+*.sh text eol=lf
+*.json text eol=lf
+*.txt text eol=lf
+*.csv text eol=lf