cue: remove block comments and slices from the language
cue: remove block comments and slices from the language

Block comments serve little purpose now embeddings
can uncomment large blocks. They also add quite a bit
of complexity.

Slices at the bytes and string level proved too confusing
and generally a bad idea for a data constraint language.
Using them only for lists hurts orthoganality and makes
them add too much baggage for their use, including
a fairly complicated interaction with default values.

Issue #87

Change-Id: I25cdd9b060f6515f2f50ff12e2b67d58625a724c
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/3244
Reviewed-by: Jonathan Amsterdam <e3d3698b2ccd5955e4adf250d0785062d0f9018b@google.com>

cuelang/cue