Fix and and or operators RT broken associativity

Extracted from #387

Without this change, the following code snippets

```ruby
a or b and c
```

and

```ruby
a[:x] = b[:x] || d(:new)
```

do not round trip.

Author: viralpraxis

lib/unparser/writer/binary.rb

@@ -52,9 +52,13 @@ def symbol_name
       end
 
       def dispatch
-        left_emitter.write_to_buffer
-        write(' ', MAP.fetch(effective_symbol), ' ')
-        visit(right)
+        if node.type.eql?(:and) && left.type.equal?(:or)
+          emit_with(KEYWORD_TOKENS)
+        else
+          left_emitter.write_to_buffer
+          write(' ', MAP.fetch(effective_symbol), ' ')
+          visit(right)
+        end
       end
 
     private

test/corpus/semantic/and.rb

@@ -6,3 +6,16 @@
 
 if a...b and c...d
 end
+
+a and b and c
+(a and b) and c
+a and (b and c)
+a and b or c
+(a and b) or c
+a and (b or c)
+a or b and c
+(a or b) and c
+a or (b and c)
+a or b or c
+(a or b) or c
+a or (b or c)

test/corpus/semantic/or.rb

@@ -0,0 +1 @@
+a[:x] = b[:x] || d(:new)