Rust Object API (#6070)

* inital commit of rust object api

* Required fields support.

* clang fallthrough

* Fix unused variables

* just don't fall through

* remove comment

* s/panic/unreachable

* Tests for object API

* Added defaults

* deleted unintentionally added files and updated .bat file

* fix bat file

* clang format

* Cargo clippy checks

* remove commented out code

* clippy allows

* Remove matches! macro since we're not yet at Rust v1.42

* install clippy in RustTest.sh

* move line

Co-authored-by: Casper Neo <cneo@google.com>

tests/include_test/include_test1_generated.rs

@@ -28,9 +28,7 @@ impl<'a> flatbuffers::Follow<'a> for TableA<'a> {
 impl<'a> TableA<'a> {
     #[inline]
     pub fn init_from_table(table: flatbuffers::Table<'a>) -> Self {
-        TableA {
-            _tab: table,
-        }
+        TableA { _tab: table }
     }
     #[allow(unused_mut)]
     pub fn create<'bldr: 'args, 'args: 'mut_bldr, 'mut_bldr>(