IDEA-57733 Remove 'vcs-impl -> lang-impl' dependency introduced by the change...

IDEA-57733    Remove 'vcs-impl -> lang-impl' dependency introduced by the change to use editor for commit message processing

1. Defined dedicated interface for spell checking-aware editor retrieval;
2. Moved actual spell checking-aware editor text field construction to 'lang-impl';
3. Commit message component retrieves spell checking-aware editor via target interface now;