Add an @member tag for documenting interface members outside of the interface

Sometimes you have a generic base interface type that you extend from, and you want to documenting a member of the extending interface without having to redeclare that member. In this instance, it would be useful to be able to document interface members in the interface's description. This is better explained in an example:

/**
 * A generic building.
 */
interface Building {
  /**
   * The total area of the building in sq. ft.
   */
  area: number;
}

// Annoying and prone to breaking if the base interface changes:

/**
 * A residential house that someone might live in.
 */
interface HouseA extends Building {
  /**
   * The total area of the house in sq. ft. House area doesn't include garages,
   * attics, and basements.
   */
  area: number;
  /**
   * The number of people living in the house.
   */
  residents: number;
}

// A preferable solution:

/**
 * A residential house that someone might live in.
 * @member area - The total area of the house in sq. ft. House area doesn't
 * include garages, attics, and basements.
 */
interface HouseB extends Building {
  /**
   * The number of people living in the house.
   */
  residents: number;
}

No files or tests are named in the issue. Start by comparing the proposed TypeScript syntax with the existing TSDoc tag specification and parser behavior; done means @member can document an inherited interface member without redeclaring it.