Remove mandatory node-space before slashdash and children block

[larsgw]

Fix #495

[tabatkins]

Could you drop a test for this?

[zkat]

A couple of interesting tests will be good yeah

[larsgw]

Okay, added.

[bgotink]

Test case braces_in_bare_id_fail.kdl becomes valid with this change so it should be updated as well.

It's content

foo123{bar}

is now equivalent to

foo123 { bar }

[larsgw]

Indeed, I forgot to patch that into kdljs while testing. Thank you @bgotink