Allow the user to choose different usernameHider text for each account
proper capitalization
Case-insensitive matching
logical blank username replacement
use profileRegex to match username in "curated by" for username hider

less brittle than .href.slice(...) === username
refactor usernameHider.getDisplayText for single point of defaults and return
usernameHider.hideAllUsernames: hide all accounts inerAccountDisplayText
usernameHider.hideAccountSwitcherUsernames

give the perAccountDisplayText treatment to usernames listed in accountSwitcher.options.accounts
usernameHider also hides .author links matching username

especially for user's posts when listed on userpages or comment pages
sanity check username in getDisplayText
use displayText's default value if nothing specified

user can put a blank space in the options if they really want a blank
sanity check username in hideUsername
Merge pull request #1782 from andytuba/1762

#1762 and then some