Alphabetize sections in buckconfig doc (Part 2 of 2)
Alphabetize sections in buckconfig doc (Part 2 of 2)

Summary:
- Move sections `[httpserver]` and `[incompatible]` between `[halide]` and `[intellij]`.
- Move `cache` entry, which was randomly located inside `[intellij]` section to where it belongs.
- Replace tab indents with space indents for `cache` entry to make it consistent with other entries in the doc source.

Reviewed By: cjhopman

fbshipit-source-id: 57dae843e7

rmaz/buck,Addepar/buck,facebook/buck,Addepar/buck,Addepar/buck,romanoid/buck,Addepar/buck,zpao/buck,rmaz/buck,JoelMarcey/buck,romanoid/buck,zpao/buck,kageiit/buck,romanoid/buck,facebook/buck,nguyentruongtho/buck,JoelMarcey/buck,kageiit/buck,nguyentruongtho/buck,romanoid/buck,facebook/buck,SeleniumHQ/buck,kageiit/buck,SeleniumHQ/buck,rmaz/buck,facebook/buck,SeleniumHQ/buck,zpao/buck,nguyentruongtho/buck,facebook/buck,SeleniumHQ/buck,zpao/buck,nguyentruongtho/buck,romanoid/buck,rmaz/buck,SeleniumHQ/buck,nguyentruongtho/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,Addepar/buck,JoelMarcey/buck,kageiit/buck,Addepar/buck,kageiit/buck,SeleniumHQ/buck,JoelMarcey/buck,facebook/buck,SeleniumHQ/buck,rmaz/buck,rmaz/buck,JoelMarcey/buck,romanoid/buck,Addepar/buck,JoelMarcey/buck,kageiit/buck,romanoid/buck,SeleniumHQ/buck,facebook/buck,SeleniumHQ/buck,Addepar/buck,JoelMarcey/buck,zpao/buck,zpao/buck,Addepar/buck,rmaz/buck,SeleniumHQ/buck,Addepar/buck,JoelMarcey/buck,rmaz/buck,romanoid/buck,JoelMarcey/buck,SeleniumHQ/buck,nguyentruongtho/buck,Addepar/buck,romanoid/buck,romanoid/buck,rmaz/buck,SeleniumHQ/buck,rmaz/buck,rmaz/buck,SeleniumHQ/buck,romanoid/buck,Addepar/buck,nguyentruongtho/buck,romanoid/buck,romanoid/buck,rmaz/buck,Addepar/buck,JoelMarcey/buck,zpao/buck,kageiit/buck,rmaz/buck