Grammar – Consistency & Cleanup 5 (#1322)

* [DTW.5]
- Remove primary_array_no_creation and replace with semantic
  rules in element_access, null_conditional_element_access
  and pointer_member_access.
- Update sample reference files & tarball to v2.3.4

* Update standard/expressions.md

Co-authored-by: Jon Skeet <skeet@pobox.com>

* Apply suggestions from code review

Co-authored-by: Jon Skeet <skeet@pobox.com>

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Co-authored-by: Nigel-Ecma <Nigel-Ecma@users.noreply.github.com>
Co-authored-by: Jon Skeet <skeet@pobox.com>

Author: Nigel-Ecma