update CHANGELOG.md

Update CHANGELOG.md for #1894, #1895, #1899, #1900, #1901, and #1905.

Author: bhcleek

CHANGELOG.md

@@ -7,10 +7,22 @@ IMPROVEMENTS:
   [[GH-1889]](https://github.com/fatih/vim-go/pull/1889)
 * Highlight `context.Context` when `g:go_highlight_extra_types` is set.
   [[GH-1903]](https://github.com/fatih/vim-go/pull/1903)
+* Run gometalinter asynchronously in Neovim.
+  [[GH-1901]](github.com/fatih/vim-go/pull/1901)
+* Run gorename asynchronously in Vim8 and Neovim.
+  [[GH-1894]](github.com/fatih/vim-go/pull/1894)
 
 BUG FIXES:
 * Fix `:GoRun %` on Windows.
   [[GH-1900]](github.com/fatih/vim-go/pull/1900)
+* Fix `go#complete#GetInfo()` to return a description of the identifier.
+  [[GH-1905]](https://github.com/fatih/vim-go/pull/1905)
+* Restore support for running tests in the Neovim terminal.
+  [[GH-1895]](https://github.com/fatih/vim-go/pull/1895)
+
+BACKWARDS INCOMPATIBILITIES:
+* Bump minimum required version of Vim to 7.4.2009.
+  [[GH-1899]](https://github.com/fatih/vim-go/pull/1899)
 
 ## 1.18 - (July 18, 2018)