General updates to Compute for style and convention

Editing the top third of the compute chapter. Mostly grammar, wording,
style, convention, etc. Some minor section-level editing to improve
readability. Watch this space for more edits on these bugs.

Change-Id: If541f4a5e20251c94f6cbf416ff7c0d0e4c66892
Partial-Bug: #1251195
Partial-Bug: #1121866
Merge "General updates to Compute for style and convention"