REL: exclude spurious sources from setuptools_scm

When setuptools_scm is installed, it adds all git-tracked files
to the sdist package.  Exclude them explicitly with MANIFEST.in.

Author: pavoljuhas

MANIFEST.in

@@ -2,7 +2,14 @@ recursive-include src *
 include SConstruct
 include AUTHORS.txt LICENSE*.txt README.rst
 recursive-exclude src *.pyc *.so
-recursive-exclude * .gitattributes .gitignore .DS_Store
+global-exclude .gitattributes .gitignore .DS_Store
 
 # Avoid user content in setup.cfg to make distribution reproducible.
 exclude setup.cfg
+
+# Exclude git-tracked files spuriously added by setuptools_scm
+exclude .coveragerc
+exclude .travis*
+prune conda-recipe
+prune devutils
+prune doc