feat(bitbake): Added installation instructions

Added github and npm links for installing the Yocto Project's official
language server for bit bake, language-server-bitbake.

lua/lspconfig/server_configurations/bitbake_ls.lua

@@ -9,9 +9,16 @@ return {
   },
   docs = {
     description = [[
+https://github.com/yoctoproject/vscode-bitbake
+https://www.npmjs.com/package/language-server-bitbake
 
-npm install -g language-server-bitbake
+Bitbake Language Server for the Yocto Project.
+
+Can be installed from npm or github.
 
+```
+npm install -g language-server-bitbake
+```
 ]],
     default_config = {
       root_dir = [[util.find_git_ancestor]],