T6111: Fix modification of String.escaped to leave UTF-8 bytes unescaped

The existing fix still passed the string as a whole to Bytes.escaped (as
does the standard libra...

T5500: adjust render function on valueless leaf and tag node values

Configtree allows for a tag node child to have values, however it is not
possible to define such...

T5317: remove mutable references

Redesign and implement version without mutable refs.

T5194: filter on files of extension .xml

T5385: catch correct errors in Xml_light Xml.parse_file

T5194: add support for reference tree

One needs to handle the pathological cases of an empty element string
and arbitrary order of chi...

cf. 4df07f8e for details

This is not applicable under the current node sorting; drop for now.

syntaxVersion elements are post-processed in the Python reference dict

T5185: drop assumption in case of a sequence of 0's

In the original implementation, it was mistakenly assumed that strings
of digits of differing le...

T5089: support for unit test of config_diff

This was a general use function that is uneeded in this simple case.

For unit tests of identity: tree = union of subtrees, one needs a
consistent ordering of values....

This is a conservative application of lexical_numeric ordering for
configtree: order nodes on in...

T5088: add lexical_numeric_compare function

T4991: add function show_diff for unified diff of configs

T4961: add name of offending node in exception Insert_error of string

This reverts commit 97d11bf2bda65c7001ad687fd088a896161fdb0d, reversing
changes made to 40f7d2af...

T4628: render tag node names containing whitespace in quotes

T4491: use empty string for name of config_tree root node

The practice of using "root" for the internal name of the root node
collides with actual nodes n...

T4235: add comments on producing delete commands

T4334: make the lexer reentrant by passing state around instead of using a shared mutable reference

instead of using a shared mutable reference

T4235: distinguish between sub(-tract) tree and delete tree

T4235: simplify return value of diff_tree

In the intial implementation, the delete tree only kept the first node
of a path not present in ...

T4235: add config tree diff algorithm

Use a modification of String.escaped to leave UTF-8 bytes unescaped