* Java: emit "signed" equivalent of unsigned default value in generated code and add "L" suffix to long default value.

* Updated generated code

* Only convert ulong to "signed" equivalent. ubyte and ushort don't need specific handling as "user facing" type is int. uint need 'L' suffix as "user facing" type is long.

* Added missing cast to primitive type of default value which is in "user facing" type in builder.add<type>() calls.

* Do not cast default value to actual type in C#.

Change-Id: I2cab7a1f68b8e643c1057e0a366572421a94ed41
Tested: on Linux.

flatc java generator: namespace_test2.fbs is missing namespace prefix for referToA2() return type (#4040)

* Fix flatc generating incorrect java/c# code for namespace_test2.fbs. In code for TableInC, method referToA2() returned type SecondTableInA instead of NamespaceA.SecondTableInA.

* Updated generated code.

* Fixed indendation.

Change-Id: Ice94f09197235cf71b41a22d0767bd7b119284e1

Tested: on Linux.

Change-Id: Iea336f75a3b6e722743563813c3c9ed9db4d02fe

Also, clean up redundant ';' at end of java classes.

Also fixed most codegenerators using the wrong namespace when multiple
namespace were used in a file, with some files not being generated.

Change-Id: Ib42969221239d7244e431cbd667ef69200fc415f
Tested: on Linux.
Bug: 29338474

Bug: 28145201
Change-Id: I5a1818c40c2f4fbd00cfec3362040407976f7a39
Tested: on Linux.

Added support for C# partial class generation when the `csharp_partial` attribute is used on a table/struct.

Fix to #360 - Updated the general generator (Java/C#) to emit fully qualified names where the referenced object isn't directly in this namespace. Added test fbs files to verify compilation.

I updated idl_gen_general.cpp to add support for generating a Get Bytes
method for a vector to the generated C# source code. Given a byte vector
field named Foo, a method named GetFooBytes() will be generated in the
C# source code that will return an ArraySegment<byte> value referencing
the vector data in the underlying ByteBuffer.

I added a method to Table.cs named __vector_as_arraysegment that is used
by the code generated by the change to the C# generator.
__vector_as_arraysegment will take the offset of the vector and will
return the ArraySegment<byte> value corresponding to the bytes that
store the vector data.

I updated FlatBuffersExampleTests.cs to add tests to validate my
implementation of Table.__vector_as_arraysegment. I added tests to
demonstrate that the bytes for the monster's name can be extracted from
the underlying byte array. I also added tests to show that
Table.__vector_as_arraysegment returns a null value if the vector is not
present in the FlatBuffer.

I used the updated flatc.exe program to regenerate the C# source files
for the MyGame example. The new Monster class includes the GetXXXBytes
methods to return the byte arrays containing data for vectors.

Also refactored the way options are stored.

Change-Id: I709ac908cd2aba396c9c282725cf1d42ccce0882
Tested: on Linux.

Fixes a bug where the logic to determine when to use a C# enum flags
both enums and vectors of enums.  This causes the C# generator to
generate code that doesn't compile for tables that contain vectors of
enums.

The fix also consolidates type generation functions a bit and adds
some additional casting functions for clarity.

```
namespace MyGame;

enum CommandType : byte {
	None = 0,
}

table Command {
	id:int;
	type:CommandType;
}
```

then generate c# files. it'll output compile error like these.

```
Assets/MyGame/Command.cs(18,39): error CS1041: Identifier expected
Assets/MyGame/Command.cs(18,39): error CS1737: Optional parameter cannot precede required parameters

16:   public static Offset<Command> CreateCommand(FlatBufferBuilder builder,
17:   int id = 0,
18:   CommandType type = (CommandType)0) {
```