feat: Add support for .gitignore

[Jason3S]

Fix: #1319

On the command line:

  --gitignore                  Ignore files matching glob patterns found in .gitignore files.
  --gitignore-root <path>      Prevent searching for .gitignore files past root.

Config:

cspell.json

    /**
     * Tells the spell checker to load `.gitignore` files and skip files that match the globs in the `.gitignore` files found.
     * @default false
     */
    useGitignore?: boolean;

    /**
     * Tells the spell checker to searching for `.gitignore` files when it reaches a matching root.
     */
    gitignoreRoot?: FsPath | FsPath[];

[capaj]

Why was this added with default: false ?
IMHO majority of people only need cspell for files checked into git.

[Kurt-von-Laven]

I assume for backwards compatibility. Perhaps the default could be changed as part of the next major version release though?

[Jason3S]

@capaj,

@Kurt-von-Laven is right, so I'll switch the default in the next major version.