* flatc --cpp-field-case option to permit camel-case field names in C++
* fixed option name; cleaned up tabs
* formatting fixed to conform to CI
* resolved comments
* fixed white space indentation
* per PR comments
* rename snake case option to unchanged for clarity, per PR comments
* cleanup of unchanged case option in C++ codegen, per PR 6669 comments
* incorporated PR feedback from vglavnyy
* cleaned up to pass Travis CI / clang format
* bumped PR to retry transient CI failure
* bumped PR to retry transient CI failure
* bump PR
* assert union type field name length > suffix, per PR 6669 comments
