MANIFEST.in: include all the files that should be included in source dist

One notable absence was README.md... :)

For the testdata/*, I now use `include_package_data=True` in setup.py, to automatically install any data files found inside package directories that are also specified in MANIFEST.in file.

I also include the Snippets, which I think should belong to the source distribution, despite not being installed as console scripts like ttx, etc.

The MANIFEST.in does not need to include itself (done by default).

MANIFEST.in

@@ -1,4 +1,14 @@
+include README.md
 include LICENSE
-include MANIFEST.in
+include NEWS
+include Snippets/*.py
+include Snippets/README.md
 include MetaTools/*.py
 include Lib/fontTools/ttLib/tables/table_API_readme.txt
+
+include *requirements.txt
+include tox.ini
+
+recursive-include Lib/fontTools *testdata/*.ttx *testdata/*.otx *testdata/*.fea
+recursive-include Lib/fontTools *testdata/*.lwfn *testdata/*.pfa *testdata/*.pfb
+recursive-include Lib/fontTools *testdata/*.xml *testdata/*.designspace

setup.py

@@ -53,19 +53,7 @@ setup(
 	packages=find_packages("Lib"),
 	py_modules=['sstruct', 'xmlWriter'],
 	extra_path='FontTools',
-	package_data={
-		'': [
-			# include files used by the test suite
-			'testdata/*.ttx',
-			'testdata/*.otx',
-			'testdata/*.fea',
-			'testdata/*.lwfn',
-			'testdata/*.pfa',
-			'testdata/*.pfb',
-			'testdata/*.xml',
-			'testdata/*.designspace',
-		]
-	},
+	include_package_data=True,
 	entry_points={
 		'console_scripts': [
 			"ttx = fontTools.ttx:main",