docgen

• Implement auto update binary (docgen)
• Display None for empty request/response body
• Change request/response body from H5->H4

• Remove default sorting, use -s to sort the collection. Solved issue: #55
• Remove default variable and template parsing, use -v flag to enable it
• Move Variables table to top for markdown documentation
• Remove author username/signature from footer

• Modify markdown template to add request example links. See #65

• Fix links to markdown anchors; Resolve issue #62

Release note:

• Add support for example request/response
• Add support for collection and environment variables
• Fix response body HTML entity problem
• Update installation script
• Add uninstall.sh script