Add identifierRegexps variable in Completer interface

[Sunwoo-Shin]

Related issues #1670

Description of changes:

added to make it possible to change the identifierRegexps variable in the Completer interface of the type script module.

Example

import {Ace} from "ace-builds";

const completers: RegexpsCompleter = {
      identifierRegexps: [/[a-zA-Z_0-9\\$\-\u00A2-\u2000\u2070-\uFFFF.]/],
      getCompletions (editor: Ace.Editor, session: Ace.EditSession, pos: Ace.Point, prefix: string, callback: Ace.CompleterCallback): void {
            ...
      }
}

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[Sunwoo-Shin]

I don't understand why the test error occurred in the following logic. (The modified file is .ts format.)
Could you please explain the reason for the error?

changes=$(git diff --name-only origin/HEAD --no-renames --diff-filter=ACMR);
if [ "$changes" == "" ]; then
      echo "checking all files";
      node node_modules/eslint/bin/eslint "lib/ace/**/*.js";
else
      changes=$(echo "$changes" | grep -P '.js$');
      echo "checking $changes";
       if [ "$changes" != "" ]; then
             node node_modules/eslint/bin/eslint $changes;
       fi
fi

[nightwing]

Thank you