[CMake] Move CMake files into their intended location so the

`contrib/cmake/bootstrap.py` script no longer needs to be executed.

The previous location of the CMake files was a compromise proposed
by @agurfinkel in #461. While this has served us well (allowing progress
to be made) over time limitations of this approach have appeared.

The main problem is that doing many git operations (e.g. pull, rebase)
means the CMake files don't get updated unless the user remembers to
run the script. This can lead to broken and confusing build system
behaviour.

This commit only does the file moving and necessary changes to
`.gitignore`. Other changes will be done in subsequent commits.

examples/tptp/CMakeLists.txt

@@ -0,0 +1,39 @@
+################################################################################
+# TPTP example
+################################################################################
+project(Z3_TPTP5 CXX)
+cmake_minimum_required(VERSION 2.8.12)
+find_package(Z3
+  REQUIRED
+  CONFIG
+  # `NO_DEFAULT_PATH` is set so that -DZ3_DIR has to be passed to find Z3.
+  # This should prevent us from accidently picking up an installed
+  # copy of Z3. This is here to benefit Z3's build sytem when building
+  # this project. When making your own project you probably shouldn't
+  # use this option.
+  NO_DEFAULT_PATH
+)
+message(STATUS "Z3_FOUND: ${Z3_FOUND}")
+message(STATUS "Found Z3 ${Z3_VERSION_STRING}")
+message(STATUS "Z3_DIR: ${Z3_DIR}")
+
+add_executable(z3_tptp5 tptp5.cpp tptp5.lex.cpp)
+target_include_directories(z3_tptp5 PRIVATE ${Z3_CXX_INCLUDE_DIRS})
+target_link_libraries(z3_tptp5 PRIVATE ${Z3_LIBRARIES})
+
+if ("${CMAKE_SYSTEM_NAME}" MATCHES "[Ww]indows")
+  # On Windows we need to copy the Z3 libraries
+  # into the same directory as the executable
+  # so that they can be found.
+  foreach (z3_lib ${Z3_LIBRARIES})
+    message(STATUS "Adding copy rule for ${z3_lib}")
+    add_custom_command(TARGET z3_tptp5
+      POST_BUILD
+      COMMAND
+        ${CMAKE_COMMAND} -E copy_if_different
+        $<TARGET_FILE:${z3_lib}>
+        $<TARGET_FILE_DIR:z3_tptp5>
+    )
+  endforeach()
+endif()
+