Refine content and improve presentation

Components are stored in the `app/styles/components/_components` directory, as
reported by @csaban.

Use inline code blocks when quoting commands or code.

Fixes #983.
Add #toc anchor to homepage

Add anchor to homepage to bypass getting started guide, as
suggested by @PaulKinlan.

Fixes #978.
Fix typo in M39 Update: meta them-color
Merge pull request #1023 from jpmedley/master

Fix typo in M39 Update: meta them-color
Merge pull request #1016 from jacquerie/issue-983

Refine content and improve presentation
Merge pull request #1022 from jacquerie/issue-978

Add #toc anchor to homepage
Optimized all PNGs
Simplified the app.yaml file and fixed some mistakes
Refactoring the build process
Merge pull request #1026 from wibblymat/app-yaml

Simplified the app.yaml file and fixed some mistakes
Merge pull request #1028 from wibblymat/images

Optimized all PNGs
Merge pull request #1027 from wibblymat/tidying

Refactoring the build process
Update documentation

Commit bad4a21 moved the Gruntfile from `src` to the root folder,
therefore `npm install` should be run there.
Merge pull request #1029 from jacquerie/tidying-doc

Update documentation
Removed some unused files
Merge pull request #1033 from wibblymat/unused

Removed some unused files
Correct page ID for use-existing-data.markdown
Merge pull request #1035 from crhym3/correct-page-id

Correct ID for use-existing-data.markdown page
Add hint not to use `sudo`

As discussed in google/web-starter-kit#547, newer developers
should know that using `sudo` for `npm install -g` is a bad idea.

Fixes #1013.
Merge pull request #1015 from jacquerie/issue-1013

Add hint not to use `sudo`