* origin/master: (61 commits)
  Add release-2.7 to covered branches
  LEGO: check in for master to temporary branch.
  LEGO: check in for master to temporary branch.
  API: fix types to undefined union (microsoft#20909)
  Fix conflict between formatting rules (microsoft#21038)
  Switch to block-bodied lambda
  Better name for deferred mapped type:ReverseMapped
  Slightly simplify getCodeActions
  Make fixCannotFindModule return an empty array if there is no code action
  In checkAndAggregateReturnExpressionTypes, treat MethodDeclaration in an object literal same as a FunctionExpression (microsoft#20052)
  Return string completions for indexed access types
  Check for unused getter/setter in classes (microsoft#21013)
  Only replace `implements` with a comma if the heritage clauses are sensible
  Refine extends-to-implements code fix
  Fix version of @types/node to 8.5.5 (microsoft#21019)
  fix microsoft#20449, insert space between decorators (microsoft#20491)
  findConfigFile can return undefined (microsoft#20556)
  Allowed trailing commas in type parameter/argument lists (microsoft#20599)
  Added localization instructions to CONTRIBUTING.md (microsoft#20451)
  Simplify marker names
  ...