Add copyright.

PiperOrigin-RevId: 259997211

Preparation for including docs in round-trip with OSS, Manual merge, review and merge docs internal-OSS

Internal change

PiperOrigin-RevId: 258587862

gmock-spec-builders.h uses std::function (in MockFunction) but did
not include <functional> to provide it. Apparently, it worked since
the header must have been included by something else but better be
safe than sorry.

Fix documentation links

PiperOrigin-RevId: 258389329

Update a broken link in a comment.

PiperOrigin-RevId: 257493975

ee3aa831 added a broken link
which results in 404. The broken part is reference to a
nonexistent file "CheatSheet.md" instead of "cheet_sheet.md".

This line directly contradicts the warning that google mock spits out on unused mock calls:
```
NOTE: You can safely ignore the above warning unless this call should not happen.  Do not suppress it by blindly adding an EXPECT_CALL() if you don't mean to enforce the call.  See https://github.com/google/googletest/blob/master/googlemock/docs/CookBook.md#knowing-when-to-expect for details.
```
One or the other should be changed, and I believe the advice in this file is incorrect.

Renaming doc files to make the file names more palatable and in preparation for including documentation in sync process

gmock_output_test has to run under python2. Bazel 0.27.0 causes this test to break. Fixing it.

PiperOrigin-RevId: 253820111

Project import generated by Copybara.

PiperOrigin-RevId: 253600369

Internal Change

PiperOrigin-RevId: 253581166

Makefiles are no longer supported. Adding pseudo-break with their impending removal to make sure that people who are interested will notice

Removing make and automake. The only supported build systems are Bazel internally and CMake community supported