styleTweaks: Add options for automatic night mode
styleTweaks: Implement basic automatic night mode handling
styleTweaks: Use value of settings
styleTweaks: Fix call to enable/disable night mode
styleTweaks: Rename switchLight for clarity
styleTweaks: Add comments and parentheses for clarity
styleTweaks: Remove random newline
styleTweaks: Add automatic night mode override

Currently broken because nightModeOverrideTime doesn't actually
persist
styleTweaks: Use RESStorage to persist night mode overrides

Currently manually set to override for one day
styleTweaks: Add option to configure length of night mode override
styleTweaks: Use more readable time format for automatic night mode
styleTweaks: Improve description of nightModeOverrideHours
styleTweaks: Add comments and clarify code
styleTweaks: Slightly adjust comments for isTimeForNightMode
styleTweaks: Comment convertTimeStringToInt method
styleTweaks: Update default nightModeOverrideHours to 8
Merge pull request #1128 from mc10/automatic-night-mode

Implement automatic night mode