gopls/doc: add vetted examples for Sublime Text
gopls/doc: add vetted examples for Sublime Text

Instructions for Sublime Text + LSP + golsp,
including examples for:
  minimal configuration
  adjusting path
  per-project settings

The per-project settings include breadcrumbs helpful
to someone working on Go itself.

Change-Id: I2fe41cd60d7327578bd5bd9999f2459e79e9be4c
Reviewed-on: https://go-review.googlesource.com/c/tools/+/325189
Trust: David Chase <ae171625adc8645b8b79b7e405a6da5aba5341e0@google.com>
Run-TryBot: David Chase <ae171625adc8645b8b79b7e405a6da5aba5341e0@google.com>
gopls-CI: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Rebecca Stambler <d7cf11e5f299d88ea8348366a9fc4f7c335c3afa@golang.org>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools