Build - SignTool Error: The specified timestamp server either could not be reached or returned an invalid response.

Can't say exactly why, but I was getting an error that didn't make any sense attempting to build this morning.

```sh
[exec] SignTool Error: The specified timestamp server either could not be reached
[exec] or returned an invalid response.
[exec] This may happen if you specify an RFC 3161 timestamp URL but used
[exec] the /t option or you specified a legacy Authenticode timestamp URL
[exec] but used the /tr option.
[exec] SignTool Warning: Signing succeeded, but an error occurred while attempting to
[exec]
[exec] timestamp: C:\codelocal\chocolatey2\code_drop\chocolatey\console\choco.exe
```

It was in https://github.com/chocolatey/choco/blob/master/.build.custom/codeSign.step. It has happily been using `/t http://timestamp.digicert.com`, but it appears maybe Digicert has taken that away as an option for `/t`.

Even though all of the documentation on Digicert appears as if we could still use `/t`, they may have made it only an RFC 3161 type of timestamp url. By the way, I find it weird/somewhat uncomfortable that these timestamp urls do not use TLS.

The fix appears to be to go through the codesign.step file and replace all instances of `/t` with `/tr`.

Is this something you are experiencing as well or is it local to me?