Docs cleanup

Additions
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* Add note about "The End"-dimension and lighting strength

* Add FAQ entry concerning mod blocks

* Add FAQ entry concerning offline viewing

* Add Pillow as alternative to PIL in the requirements

Changes
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* Restructured the Config File Specification

* As result of bullet point above, grouped options together thematically to make them easier to find.

* Minor fixes to wording of index page and README

* Change version from 0.10 to 0.11 and bump the copyright date by 2 years as well.