[Nim] Bfbs Nim Generator (#7534)

* Bfbs Nim Generator

* Remove commented out tests

* add missing line to idl.h

* Commit python reflection changes

* Commit python reflection changes and move tests

* Remove default string addition

* Move tests to python file

* Fix element size check when element is table

* remove whitespace changes

* add element_type docs and commit further to namer and remove kkeep

* Bfbs Nim Generator

* Remove commented out tests

* add missing line to idl.h

* Commit python reflection changes

* Commit python reflection changes and move tests

* Remove default string addition

* Move tests to python file

* Fix element size check when element is table

* remove whitespace changes

* add element_type docs and commit further to namer and remove kkeep

* remove unused variables

* added tests to ci

* added tests to ci

* fixes

* Added reflection type Field, Variable to namer

* Moved reflection namer impl to bfbsnamer

* Remove whitespace at end of line

* Added nim to generated code

* Revert whitespace removal

Co-authored-by: Derek Bailey <derekbailey@google.com>

tests/MyGame/Example/Vec3.nim

@@ -0,0 +1,52 @@
+#[ MyGame.Example.Vec3
+  Automatically generated by the FlatBuffers compiler, do not modify.
+  Or modify. I'm a message, not a cop.
+
+  flatc version: 22.9.29
+
+  Declared by  : 
+  Rooting type : MyGame.Example.Monster ()
+]#
+
+import Color as MyGame_Example_Color
+import Test as MyGame_Example_Test
+import flatbuffers
+
+type Vec3* = object of FlatObj
+func x*(self: Vec3): float32 =
+  return Get[float32](self.tab, self.tab.Pos + 0)
+func `x=`*(self: var Vec3, n: float32): bool =
+  return self.tab.Mutate(self.tab.Pos + 0, n)
+func y*(self: Vec3): float32 =
+  return Get[float32](self.tab, self.tab.Pos + 4)
+func `y=`*(self: var Vec3, n: float32): bool =
+  return self.tab.Mutate(self.tab.Pos + 4, n)
+func z*(self: Vec3): float32 =
+  return Get[float32](self.tab, self.tab.Pos + 8)
+func `z=`*(self: var Vec3, n: float32): bool =
+  return self.tab.Mutate(self.tab.Pos + 8, n)
+func test1*(self: Vec3): float64 =
+  return Get[float64](self.tab, self.tab.Pos + 16)
+func `test1=`*(self: var Vec3, n: float64): bool =
+  return self.tab.Mutate(self.tab.Pos + 16, n)
+func test2*(self: Vec3): MyGame_Example_Color.Color =
+  return MyGame_Example_Color.Color(Get[uint8](self.tab, self.tab.Pos + 24))
+func `test2=`*(self: var Vec3, n: MyGame_Example_Color.Color): bool =
+  return self.tab.Mutate(self.tab.Pos + 24, n)
+func test3*(self: Vec3): MyGame_Example_Test.Test =
+  return MyGame_Example_Test.Test(tab: Vtable(Bytes: self.tab.Bytes, Pos: self.tab.Pos + 26))
+proc Vec3Create*(self: var Builder, x: float32, y: float32, z: float32, test1: float64, test2: MyGame_Example_Color.Color, test3_a: int16, test3_b: int8): uoffset =
+  self.Prep(8, 32)
+  self.Pad(2)
+  self.Prep(2, 4)
+  self.Pad(1)
+  self.Prepend(test3_b)
+  self.Prepend(test3_a)
+  self.Pad(1)
+  self.Prepend(test2)
+  self.Prepend(test1)
+  self.Pad(4)
+  self.Prepend(z)
+  self.Prepend(y)
+  self.Prepend(x)
+  return self.Offset()