Update to 1.23:

1.23  Mon Oct 20 18:12:00 2014
- Change output format when using node2string(), which is called by tree2string().
Indentation which used to be '|---' is now '|--- '. So, a tree which used to be printed as:
|---:default
|  |---::=
|  |---action
|  |---=>
|  |---[values]
Is now printed as:
|--- :default
|  |--- ::=
|  |--- action
|  |--- =>
|  |--- [values]
This makes the difference between node names ''/'-', '1'/'-1', etc, much clearer.
Apologies to anyone who runs tests which compare the output with pre-existing files.

(wiz)