Fix #78

[wafer-li]

Only load math script in homepage whose posts contain mathjax: true
and the page with mathjax: true

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines.
• Tests for the changes have been added (for bug fixes / features).
  • Muse | Mist have been tested.
  • Pisces | Gemini have been tested.
• Docs have been added / updated (for bug fixes / features).

PR Type

What kind of change does this PR introduce?

• Bugfix.
• Feature.
• Code style update (formatting, local variables).
• Refactoring (no functional changes, no api changes).
• Build related changes.
• CI related changes.
• Documentation content changes.
• Other... Please describe:

What is the current behavior?

Math script will be loaded in tags and achives pages with no mathjax: true

Issue Number(s): #78

What is the new behavior?

Math script will only be loaded in two situations:

1. The current page contains a front matter mathjax: true

2. The current page is homepage and it has a least one post which contains the mathjax: true front matter

• Screens with this changes:

Homepage with no post contains mathjax: true:

Homepage with post contains mathjax: true:

Post with no mathjax: true:

Post with mathjax: true:

• Link to demo site with this changes: N/A

How to use?

In NexT _config.yml:

No changes of config file.

Does this PR introduce a breaking change?

• Yes.
• No.

[wafer-li]

@tsanie Mist all right?

[tsanie]

seems no problem.