Reorder items on settings page and improve wording

Someone pointed out there is confusion over the setting to 'automatically follow someone who follows you', not realising this is the same as sharing with someone. I have therefore clarified this wording, making the terminology consistent with use elsewhere ('sharing with' instead of 'following'). 

I have also reordered some items and made wording more clear in other instances, and put 'Re-enable Getting Started' under the same heading as 'Show Community Spotlight in stream'.