Merge remote-tracking branch 'origin/v2' into slang

# Conflicts:
#	package-lock.json
#	package.json
#	tests/format/BasicIterator/__snapshots__/format.test.js.snap
#	tests/format/BasicIterator/jsfmt.spec.js
#	tests/format/BinaryOperators/__snapshots__/format.test.js.snap
#	tests/format/BinaryOperators/jsfmt.spec.js
#	tests/format/Comments/jsfmt.spec.js
#	tests/format/EnumDefinitions/__snapshots__/jsfmt.spec.js.snap
#	tests/format/FunctionDefinitions/__snapshots__/format.test.js.snap
#	tests/format/FunctionDefinitions/jsfmt.spec.js
#	tests/format/ImportDirective/__snapshots__/jsfmt.spec.js.snap
#	tests/format/IndexOf/__snapshots__/format.test.js.snap
#	tests/format/IndexOf/jsfmt.spec.js
#	tests/format/ModifierInvocations/__snapshots__/format.test.js.snap
#	tests/format/ModifierInvocations/jsfmt.spec.js
#	tests/format/Pragma/Pragma.sol
#	tests/format/Pragma/__snapshots__/format.test.js.snap
#	tests/format/Proxy/__snapshots__/format.test.js.snap
#	tests/format/Proxy/jsfmt.spec.js
#	tests/format/StyleGuide/__snapshots__/format.test.js.snap
#	tests/format/StyleGuide/jsfmt.spec.js
#	tests/format/Tuples/__snapshots__/format.test.js.snap
#	tests/format/Tuples/__snapshots__/jsfmt.spec.js.snap
#	tests/format/Tuples/jsfmt.spec.js
#	tests/format/Tupples/__snapshots__/jsfmt.spec.js.snap

Author: Janther

tests/format/FunctionDefinitionsV0.5.0/FunctionDefinitions.sol

@@ -0,0 +1,4 @@
+contract FunctionDefinitions {
+  function () external {}
+  function () external payable {}
+}