keep userbar pinned to header (not floating) on subs which style userbar top
migrate: Slightly adjust error message
Merge pull request #1291 from andytuba/issue_1291

pinHeader userbar floats not-at-top on subreddits which customize userbar position
Merge pull request #1292 from mc10/migrate

migrate: Slightly adjust error message
nightMode: Create separate night mode module
nightMode: Add night mode file to browsers
styleTweaks: Minor copyedit to option
nightMode: Begin migrating from styleTweaks to nightMode
migrate: Migrate nightMode settings
nightMode: Rename useSubredditStyleInDarkMode

Description slightly altered as well to reflect the change.
nightMode: Improve description of lightSwitch
styleTweaks: Use === instead of ==
migrate: Add moveStorage function for moving RESStorage options
migrate: Add moveStorageWithFunction function
nightMode: Migrate RESmodules.styleTweaks.nightModeWhitelist
styleTweaks: Fix spacing
styleTweaks: Slightly adjust use of jQuery variable
styleTweaks: Replace `this` with modules['nightMode']
nightMode: Reorder options
nightMode: Rename lightSwitch to nightSwitch and update description