Remove the default .tool-versions file (#351)

* Remove the default .tool-versions file

By removing the .tool-versions file it makes it easier for users to use
their system installed elixir and erlang versions.

There is some related discussion in
#344 but most of the
discussion was in Slack.

* Update changelog

Author: axelson

.release-tool-versions

@@ -0,0 +1,7 @@
+# This file contains the recommended versions for building releases for
+# elixir-ls.
+#
+# The versions selected here are the versions that are used to build a binary
+# release for distribution
+elixir 1.8.2-otp-21
+erlang 21.3.8.17

.tool-versions

@@ -19,6 +19,7 @@ House keeping:
 - Update the dialyzer section in the readme (thanks [Serenity597](https://github.com/Serenity597)) [#323](https://github.com/elixir-lsp/elixir-ls/pull/323)
 - Add vim-lsp to plugin list (thanks [Thanabodee Charoenpiriyakij](https://github.com/wingyplus)) [#340](https://github.com/elixir-lsp/elixir-ls/pull/340)
 - Cleanup test output (thanks [Jason Axelson](https://github.com/axelson)) [#347](https://github.com/elixir-lsp/elixir-ls/pull/347)
+- Remove the default .tool-versions file (thanks [Jason Axelson](https://github.com/axelson)) [#351](https://github.com/elixir-lsp/elixir-ls/pull/351)
 
 Note: `MIX_TARGET` support was added in 0.5.0 but wasn't added to the changelog until later:
 - Support `MIX_TARGET` so the language server can have target specific contexts, like with Nerves (thanks [Jon Carstens](https://github.com/jjcarstens)) [#299](https://github.com/elixir-lsp/elixir-ls/pull/299)

CHANGELOG.md

@@ -18,6 +18,7 @@ Pull down the latest master
 Make the tag from the new master
 Push the tag (`git push upstream --tags`)
 - `rm -rf _build release`
+- `cp .release-tool-versions .tool-version`
 - `mix elixir_ls.release`
 - `cd release`
 - `zip elixir-ls.zip *`