docs: fix doc issues (#2497)

Author: xgirma

packages/docs/docs/guide/assets.md

@@ -2,7 +2,7 @@
 
 ## Relative URLs
 
-All Markdown files are compiled into Vue components and processed by [webpack](http://webpack.js.org/). You can, **and should **, reference any assets using relative URLs:
+All Markdown files are compiled into Vue components and processed by [webpack](http://webpack.js.org/). You can, **and should**, reference any assets using relative URLs:
 
 ``` md
 ![An image](./image.png)

packages/docs/docs/guide/directory-structure.md

@@ -54,7 +54,7 @@ When customizing `templates/ssr.html`, or `templates/dev.html`, it’s best to e
 
 ## Default Page Routing
 
-Here we use the `docs` directory as the `targetDir` (see [Command-line Interface](../api/cli.md#usage)). All the "Relative Paths" below are relative to the `docs` directory. Add `scripts` in `package.json` which is located in your project's root directory:
+Here we use the `docs` directory as the `targetDir` (see [Command-line Interface](../api/cli.md#usage)). All the "Relative Paths" below are relative to the `docs` directory. Add `scripts` in `package.json` which is located in your project’s root directory:
 
 ```json
 {

packages/docs/docs/guide/frontmatter.md

@@ -152,4 +152,4 @@ See [Default Theme Config > Built-in Search](../theme/default-theme-config.html#
 - Type: `array`
 - Default: `undefined`
 
-See [Default Theme Config > Built-in Search](../theme/default-theme-config.html#built-in-search). for details.
+See [Default Theme Config > Built-in Search](../theme/default-theme-config.html#built-in-search) for details.

packages/docs/docs/guide/global-computed.md

@@ -4,7 +4,7 @@ In VuePress, some core [computed properties](https://vuejs.org/v2/guide/computed
 
 ## $site
 
-This is the `$site` value of the site you're currently reading:
+This is the `$site` value of the site you’re currently reading:
 
 ``` json
 {
@@ -25,7 +25,7 @@ This is the `$site` value of the site you're currently reading:
 
 ## $page
 
-This is the `$page` value of the page you're currently reading:
+This is the `$page` value of the page you’re currently reading:
 
 ``` json
 {

packages/docs/docs/guide/markdown.md

@@ -245,7 +245,7 @@ export default {
 </ul>
 ```
 
-A [list of valid languages](https://prismjs.com/#languages-list) is available on Prism's site.
+A [list of valid languages](https://prismjs.com/#languages-list) is available on Prism’s site.
 
 ## Line Highlighting in Code Blocks
 

packages/docs/docs/guide/permalinks.md

@@ -50,7 +50,7 @@ module.exports = {
 
 You can also set set a permalink for a single page only. This overrides the aforementioned global setting:
 
-📝 __hello.md__:
+📝 **hello.md**:
 
 ```markdown
 ---