BaseTools: Add FMMT Python Tool

The FMMT python tool is used for firmware files operation, which has
the Fv/FFs-based 'View'&'Add'&'Delete'&'Replace' operation function:

1.Parse a FD(Firmware Device) / FV(Firmware Volume) / FFS(Firmware Files)
2.Add a new FFS into a FV file (both included in a FD file or not)
3.Replace an FFS in a FV file with a new FFS file
4.Delete an FFS in a FV file (both included in a FD file or not)
5.Extract the FFS from a FV file (both included in a FD file or not)

This version of FMMT Python tool does not support PEIM rebase feature,
this feature will be added in future update.

Currently the FMMT C tool is saved in edk2-staging repo, but its
quality and coding style can't meet the Edk2 quality, which is hard to
maintain (Hard/Duplicate Code; Regression bugs; Restrict usage).

The new Python version keeps same functions with origin C version. It
has higher quality and better coding style, and it is much easier to
extend new functions and to maintain.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1847
RFC Link: https://edk2.groups.io/g/devel/message/82877
Staging Link: https://github.com/tianocore/edk2-staging/tree/PyFMMT

Cc: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Signed-off-by: Yuwei Chen <yuwei.chen@intel.com>
Reviewed-by: Bob Feng <bob.c.feng@intel.com>
Acked-by: Liming Gao <gaoliming@byosoft.com.cn>

BaseTools/Source/Python/FMMT/__init__.py

@@ -0,0 +1,6 @@
+## @file
+# This file is used to define the FMMT dependent external tool.
+#
+# Copyright (c) 2021-, Intel Corporation. All rights reserved.<BR>
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##