New features and bug fixes for theme vexo

[taeshahn]

Hi, @yanm1ng.
Thank you for sharing this awesome theme for Hexo.

I added some features and fixed bugs a bit.
See below for details :)

The Details

1. Added Utterances as another comment system option.
   Gitment didn't work for me. I think I misconfigured something maybe...
   So I made Utterances also available as another comment system.

2. Added Local Search using hexo-generator-searchdb.
   Now we can search in our own blog. My blog using local search is HERE for your reference :)
   The instruction for configuration is updated on README.md.

3. Series Layout using post.categories.
   Very similar to the Tags layout.
   However, it groups posts according to categories, not tags, and sorts the category labels alphabetically and articles by the published date.

4. Fixed Some bugs.

   • Hyperlink in ToC doesn't work when it contains non-English characters such as Korean. (URL decoding)
   • Hyperlink for Tag label doesn't work when the tag contains special symbols such as , ', #. (Escaping Symbols)
   • Removed or replaced some broken links for images.
   • Replace hard-coded Chinese characters with English.

5. Minor CSS changes.

6. Edit README.md for updating instructions for Utterances and Local Search.

Please let me know if you have any questions⭐

The List of New/Updated Sources

File Path/Name	ChangeType	Utterances	Local Search	Series (Category Layout)	Broken Link	Hard-coded Chinese	Symbols Escaping for Tags/Categories Hyperlink	URL Decoding for ToC HiperLink	CSS	[#] NOTE
_config.yml	Modified	O	O		O#					Removed
layout/page.ejs	Modified	O
source/js/local-search.js	New		O
source/css/_partial/search.styl	New		O
layout/_partial/head.ejs	Modified		O
layout/_partial/header.ejs	Modified		O
source/css/style.styl	Modified		O	O					O#	[modify] display: inline-grid
layout/_third-party/localsearch.ejs	New		O
layout/_partial/search/localsearch_button.ejs	New		O
layout/_partial/search/localsearch_view.ejs	New		O
_source/series/	New			O
layout/series.ejs	New			O
source/css/_partial/categories.styl	New			O
source/js/script.js	Modified			O			O#	O		Escaping Special symbols in Tag
layout/project.ejs	Modified					O#				Replace 开源项目 with GitHub Open Source Projects
layout/tags.ejs	Modified					O#				Replace 标签检索 with Tag Retrieval
layout/archive.ejs	Modified					O#				Replace 文章归档 with Archives
source/css/images/error_icon.png	New				O#					Replaced
source/css/_partial/about.styl	Modified								O#	[remove] opacity: 0.25
source/css/_partial/catalog.styl	Modified								O#	[modify] ToC margin/padding
source/css/_partial/footer.styl	Modified								O#	[modify] max-width: 960px
source/css/_partial/header.styl	Modified								O#	[remove] border-bottom
source/css/_partial/markdown.styl	Modified								O#	[modify] overflow-x, font-size

[yanm1ng]

👍