Making a more sane .gitignore

Summary:
Cleaning up .gitignore \0/

Note: deliberately excluded the ignore for yarn.lock as it makes more sense to be able to see the differences from HEAD and allow us to potentially upgrade them if necessary
Closes facebookarchive#1666

Reviewed By: flarnie

Differential Revision: D7085339

Pulled By: flarnie

fbshipit-source-id: 1699373d5b3d64aa3954b0ed7b21e8aa090e3268

.gitignore

@@ -1,17 +1,7 @@
-/dist/
-/lib/
-/node_modules/
-/examples/tex/node_modules/
-/examples/draft-0-9-1/tex/node_modules/
-/examples/draft-0-10-0/tex/node_modules/
-/examples/draft-0-9-1/universal/static
-/examples/draft-0-9-1/universal/node_modules
-/examples/draft-0-9-1/universal/yarn.lock
-/examples/draft-0-10-0/universal/static
-/examples/draft-0-10-0/universal/yarn.lock
-/examples/draft-0-10-0/universal/node_modules
-/website/build/
-/website/node_modules/
-/website/src/lib/
-/website/src/docs/
+static/
+dist/
+lib/
+build/
+node_modules
+website/src/docs/
 npm-debug.log