Improve formatter

[janmasrovira]

• Closes The Juvix formatter works poorly with multi-line ifs #1793.

Now, if the body of a function clause does not fit in a line, the body will start indented in the next line.

The example presented in the linked issue is now formatted thus:

  go n s :=
    if
      (s < n)
      (go (sub n 1) s)
      (go n (sub s n) + go (sub n 1) s);