Updated RELEASES.md for 1.39.0

[XAMPPRocky]

Rendered

r? @Mark-Simulacrum
cc @rust-lang/release

[JohnCSimon]

Ping from triage:
@Mark-Simulacrum this PR looks like it's still waiting on review.
Thanks.

[Mark-Simulacrum]

@bors r+

[bors]

📌 Commit 9e55d6fe0c6675fc84f923f5f0695daa0544aafe has been approved by Mark-Simulacrum

[Mark-Simulacrum]

@bors r-

Actually, could you squash this? I was going to do that myself and push it up but it seems I can't for some reason :/

[XAMPPRocky]

@bors r+

[bors]

📌 Commit 5fb4111 has been approved by XAMPPRocky

[XAMPPRocky]

@Mark-Simulacrum Done.

[bors]

⌛ Testing commit 5fb4111 with merge 7e2b84ee4e4d0b7fef834ea834822cb66d1be26e...

[rust-highfive]

The job x86_64-mingw-1 of your PR failed (pretty log, raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

2019-11-01T10:03:51.3114564Z do so (now or later) by using -b with the checkout command again. Example:
2019-11-01T10:03:51.3117158Z 2019-11-01T10:03:51.3117359Z git checkout -b <new-branch-name>
2019-11-01T10:03:51.3117432Z 2019-11-01T10:03:51.3117509Z HEAD is now at 7e2b84ee4 Auto merge of #64878 - XAMPPRocky:relnotes-1.39.0, r=XAMPPRocky
2019-11-01T10:03:51.3490847Z ##[section]Starting: Decide whether to run this job
2019-11-01T10:03:51.3614973Z ==============================================================================
2019-11-01T10:03:51.3615073Z Task : Bash
2019-11-01T10:03:51.3615148Z Description : Run a Bash script on macOS, Linux, or Windows
---
2019-11-01T10:03:52.8061158Z environment variables:
2019-11-01T10:03:52.8061201Z 2019-11-01T10:03:52.8061231Z 2019-11-01T10:03:52.8061285Z 2019-11-01T10:03:52.8061353Z ### [Rendered](https://github.com/XAMPPRocky/rust/blob/relnotes-1.39.0/RELEASES.md)
2019-11-01T10:03:52.8061517Z AGENT_DISABLELOGPLUGIN_TESTFILEPUBLISHERPLUGIN=true
2019-11-01T10:03:52.8061604Z AGENT_DISABLELOGPLUGIN_TESTRESULTLOGPLUGIN=true
2019-11-01T10:03:52.8061667Z AGENT_HOMEDIRECTORY=C:\agents\2.159.2
2019-11-01T10:03:52.8061745Z AGENT_ID=517
---
2019-11-01T10:03:52.8067043Z BUILD_SOURCEBRANCHNAME=auto
2019-11-01T10:03:52.8067118Z BUILD_SOURCESDIRECTORY=D:\a\1\s
2019-11-01T10:03:52.8067194Z BUILD_SOURCEVERSION=7e2b84ee4e4d0b7fef834ea834822cb66d1be26e
2019-11-01T10:03:52.8067279Z BUILD_SOURCEVERSIONAUTHOR=bors
2019-11-01T10:03:52.8067357Z BUILD_SOURCEVERSIONMESSAGE=Auto merge of #64878 - XAMPPRocky:relnotes-1.39.0, r=XAMPPRocky
2019-11-01T10:03:52.8067507Z COBERTURA_HOME=C:\cobertura-2.1.1
2019-11-01T10:03:52.8067590Z COMMONPROGRAMFILES=C:\Program Files\Common Files
2019-11-01T10:03:52.8067664Z COMMON_TESTRESULTSDIRECTORY=D:\a\1\TestResults
2019-11-01T10:03:52.8067743Z COMPUTERNAME=fv-az425
---
2019-11-01T11:33:26.8152111Z 2019-11-01T11:33:26.8152169Z 2019-11-01T11:33:26.8829793Z failed to run: D:\a\1\s\build\bootstrap\debug\bootstrap test --exclude src/test/ui --exclude src/test/compile-fail
2019-11-01T11:33:26.8829974Z Build completed unsuccessfully in 1:20:32
2019-11-01T11:33:26.9392950Z make: *** [Makefile:89: ci-mingw-subset-1] Error 1
2019-11-01T11:33:26.9979917Z local time: Fri Nov 1 11:33:26 CUT 2019
2019-11-01T11:33:27.4171119Z network time: Fri, 01 Nov 2019 11:33:27 GMT
2019-11-01T11:33:27.4171367Z == end clock drift check ==
2019-11-01T11:33:27.4838195Z 2019-11-01T11:33:27.4838195Z 2019-11-01T11:33:27.7883367Z ##[error]Bash exited with code '2'.
2019-11-01T11:33:27.8316371Z ##[section]Starting: Checkout
2019-11-01T11:33:27.9239814Z ==============================================================================
2019-11-01T11:33:27.9239920Z Task : Get sources
2019-11-01T11:33:27.9240031Z Description : Get sources from a repository. Supports Git, TfsVC, and SVN repositories.

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[bors]

💔 Test failed - checks-azure

[Mark-Simulacrum]

@bors retry

(This is not actually high priority, as we're not blocked on it -- this PR has already landed into beta and as such will be promoted into stable tomorrow)

[bors]

⌛ Testing commit 5fb4111 with merge cba9368...

[bors]

☀️ Test successful - checks-azure
Approved by: XAMPPRocky
Pushing cba9368 to master...