GitLab

apk_size_regressions.md: Make use of size trybot.
html_report_faq.md: Link to README.md
README.md: Add resource_sizes.py and size trybot
README.md: Document all "Overhead:" symbols.
README.md: Mention Bloaty McBloatface

Change-Id: I4cab3b7cd4c711931e9cae102e2354408cfbdd02
Reviewed-on: https://chromium-review.googlesource.com/c/1278721
Commit-Queue: agrieve <agrieve@chromium.org>
Reviewed-by: Mohamed Heikal <mheikal@chromium.org>
Reviewed-by: Eric Stevenson <estevenson@chromium.org>
Reviewed-by: Samuel Huang <huangs@chromium.org>
Reviewed-by: Peter Wen <wnwen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599719}