Implicit blocks for else.

Many people want the benefits of early return. There's a way to get many of them without the complexity of early return:

We can simply allow the else blocks to not be wrapped in { }.
Instead of this:

let fn = (shouldRun, name) => {
  if (!shouldRun()) {
    []
  } else {
  	if (name == "test") {
      []
    } else {
      if (String.length(name) > 80) {
        ["name too long"]
      } else {
        []    
      };
    };
  };
};

We could allow:

let fn = (shouldRun, name) => {
  if (!shouldRun()) {
    []
  } else
  if (name == "test") {
    []
  } else
  if (String.length(name) > 80) {
    ["name too long"]
  } else {
    []
  }
};

The issue names no files, tests, or entry points. Start by locating the Reason syntax and parser handling if/else expressions, then review existing grammar tests. Done means the unbraced else-if form is accepted while the existing braced form continues to work.