Migrate build to CMake and standard github workflows

Replace makefiles with CMakeLists.txt. This will allow for IDE and
platform agnostic builds of FFF.

Update the CI for FFF to use github workflows which don't depend on MS VC.
The workflow added will verify the pull requests sent to master buy
running 'buildandtest' which mirrors the developer workflow.

Signed-off-by: Yuval Peress <peress@google.com>

CMakeLists.txt

@@ -0,0 +1,34 @@
+# Copyright 2022 Google LLC
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+project(fff)
+
+set(CMAKE_CXX_STANDARD 11)
+
+# Add the gtest library which will be used below
+add_subdirectory(gtest)
+
+# Enable ctest
+enable_testing()
+
+# Generate fff.h if fakegen.rb changed
+add_custom_command(
+  OUTPUT
+    ${CMAKE_CURRENT_LIST_DIR}/fff.h
+  COMMAND
+    ruby ${CMAKE_CURRENT_LIST_DIR}/fakegen.rb >> ${CMAKE_CURRENT_LIST_DIR}/fff.h
+  DEPENDS
+    ${CMAKE_CURRENT_LIST_DIR}/fakegen.rb
+    ${CMAKE_CURRENT_LIST_DIR}/LICENSE
+)
+add_custom_target(fff_h DEPENDS ${CMAKE_CURRENT_LIST_DIR}/fff.h)
+
+# Add an interface library for fff.h
+add_library(fff INTERFACE)
+add_dependencies(fff fff_h)
+target_include_directories(fff INTERFACE ${CMAKE_CURRENT_LIST_DIR})
+
+# Add tests and samples
+add_subdirectory(test)
+add_subdirectory(examples)