Changes subParser for headers to require a space or tab
character before a header, so that
```md
# Header
```
Is a valid header, whereas:
```md
#Header
```
Is **not** rendered as a header.
Enable parsing markdown inside HTML blocks if those blocks have an attribute called markdown="1".
This feature is EXPERIMENTAL! As such, the behavior might change on future releases.
Closes#178
When literalMidWordUnderscoresis set to true, em and strong tags that start or end a paragraph don't get parsed as such.
This fixes this issue.
Closes#174
Github Flavored Markdown supports tasklist by `[x]` or `[ ]` after list item marker.
This commit adds this feature to showdown through an option called "tasklists".
Related to #164
GFM support fenced codeblocks. Showdown, since very early, adopted this too.
It is now possible to disable GFM codeblocks with the option "ghCodeBlocks" set to false.
It is enabled by default
Github Flavored Markdown supports a specific table syntax. Table support was already available as an extension.
With this commit, the feature was moved to core, adding this feature to showdown through an option called "tables".
Related to #164
Github Flavored Markdown supports strikethrough (`<del>`) syntax using double tilde `~~` delimiters.
This commit adds this feature to showdown through an option called "strikethrough".
Related to #164
Github Flavored Markdown does not parse underscores in the middle of a word as emphasis/bold.
This commit adds this feature to showdown through an option called "literalMidWordUnderscores".
Related to #164
Github Flavored Markdown detects urls and mails embeded in the text without any extra markup or delimiter.
This commit adds this feature to showdown through an option called "simplifiedAutoLink".
Related to #164
This feature allows users to define the image dimensions using markdown syntax:
```
```
To enable this feature, use the option `parseImgDimensions`.
Closes#143
