* /user/download: remove instruction to compile and run skia
tests - moved to /user/quick/${OS}
* /user/quick/desktop: move Gyp options to a section in the
FAQ (distracts from quick start narritive).
* /user/tips: reformat, rewrite.
NOTRY=true
DOCS_PREVIEW= https://skia.org/?cl=1443653002
Review URL: https://codereview.chromium.org/1443653002
- /user/quick/desktop to bring together all common information for
using Skia on desktop OSes. Remove duplication.
- Replace all instances of call ing gyp_skia directly with calling
`python bin/sync-and-gyp`. This is more correct on Windows
- Remove outdated linux prerequisite packages
- Formatting, formatting, formatting.
- Note command-line syntax differences in Windows
- SampleApp.app is no longer a bundle on MacOS
NOTRY=true
DOCS_PREVIEW= https://skia.org/?cl=1439493003
Review URL: https://codereview.chromium.org/1439493003
