Career bonus rebalancing for servant/stewardess

Servant career bonuses are really rare (and, wierdly, far rarer than Stewardess career bonuses). This MR makes an attempt at correcting this balance issue, as follows:

1. Changes five non-leadership careers which currently grant a Stewardess bonus (a barista, a bartender, a caregiver, a personal assistant, and an air hostess) to instead grant a Servant bonus.
2. Grants the Servant bonus to the (rare) menial career a launderer.
3. Adds a new career, a bellhop, granting a Servant bonus, for very young, young, and uneducated slaves.
4. Replaces an air hostess in the Stewardess bonus career list with the new educated career a purser (which is the equivalent leadership role).

Essentially this is a net gain of seven careers for Servant (added to the current six) and a net loss of three careers for Stewardess (out of twenty-one previously). Stewardess still has more bonus-granting careers than any other leadership role, and Servant still has less than any other non-leadership role, but it's at least a little better, and I think the bonuses make more sense.

Players with ongoing games may want to double-check their Stewardess, as she will have lost her leadership bonus if she had one of the five careers which were demoted to granting Servant bonuses instead.

Also fixes a few random missing spaces.