message: Remove index.builtinTypes and fix doc
diff: #include <string>
  /*
  -The language client plugin needs to send some initialization options to the
  -cquery language server. The only required option is cacheDirectory, which is
  -where index files will be stored.
  +The language client plugin needs to send initialization options in the
  +`initialize` request to the cquery language server. The only required option is
  +`cacheDirectory`, which is where index files will be stored.
  {
  "initializationOptions": {
  - "cacheDirectory": "/tmp/cquery",
  + "cacheDirectory": "/tmp/cquery"
  }
  }
  -If necessary, these options can also be passed via the command line option
  ---init, for example,
  +If necessary, the command line option --init can be used to override
  +initialization options specified by the client. For example, in shell syntax:
  - --init='{"enableComments": 2}'
  + '--init={"indexWhitelist": ["."], "index": {"comments": 2}}'
  */
  struct Config {
  // Root directory of the project. **Not available for configuration**
  @@ -51,15 +51,12 @@ struct Config {
  // Additional arguments to pass to clang.
  std::vector<std::string> extraClangArguments;
  - // If a translation unit's absolute path matches any EMCAScript regex in this
  - // list, it will be indexed. The whitelist takes priority over the blacklist.
  - // To only index files in the whitelist, make indexBlacklist match
  - // everything, ie, set it to ".*".
  + // If a translation unit's absolute path matches any EMCAScript regex in the
  + // whitelist, or does not match any regex in the blacklist, it will be indexed.
  + // To only index files in the whitelist, add ".*" to the blacklist.
  + // `std::regex_search(path, regex, std::regex_constants::match_any)`
  //
  - // You probably want to begin the regex using .* because the passed paths are
  - // absolute.
  - //
  - // Example: .*/ash/*
  + // Example: `ash/.*\.cc`
  std::vector<std::string> indexWhitelist;
  std::vector<std::string> indexBlacklist;
  // If true, project paths that were skipped by the whitelist/blacklist will
  @@ -141,8 +138,6 @@ struct Config {
  Completion completion;
  struct Index {
  - bool builtinTypes = false;
  -
  // 0: none, 1: doxygen, 2: all comments
  // Plugin support for clients:
  // - https://github.com/emacs-lsp/lsp-ui
  @@ -159,7 +154,7 @@ struct Config {
  };
  MAKE_REFLECT_STRUCT(Config::ClientCapability, snippetSupport);
  MAKE_REFLECT_STRUCT(Config::Completion, filterAndSort);
  -MAKE_REFLECT_STRUCT(Config::Index, builtinTypes, comments);
  +MAKE_REFLECT_STRUCT(Config::Index, comments);
  MAKE_REFLECT_STRUCT(Config,
  compilationDatabaseDirectory,
  cacheDirectory,
  