fix double url encoding in path

[tarunKoyalwar]

Proposed Changes

• Bump utils v0.0.4 -> v0.0.7
• Adds .Prepare() method which applies a hot patch that prevents double url encoding

closes #50

[tarunKoyalwar]

Current Patch

If path contains url encoded chars -> decode them and pass it to http.Request -> http.Request internally re-encodes them

EdgeCase

• integrity of percent encoding payload is not guaranteed since encoding is done internally (rarecase)

What is Percent Encoding ??

• in url encoding . if special character (ex: space or =) that are reserved in RFC are found it converts them to %xx this is url encoding
• in percent encoding . all characters (even if they are not reserved ) are converted to %xx
  Ex: A is not a reserved character but in percent encoding it is written as %41 .
• so if url is scanme.sh/%41 integrity is not preserved and is converted to scanme.sh/A
• Above mentioned is a rare case but normal payloads like
  scanme.sh/%20%2e%0a remains the same (edited)

Note

• payload integrity is only guaranteed in unsafe raw requests

[tarunKoyalwar]

$ https://scanme.sh/%00/path?param=true

GET /%00/path?param=true HTTP/1.1
Host: scanme.sh
User-Agent: Go-http-client/1.1
Accept-Encoding: gzip

[Mzack9999]

lgtm - Few suggestions:

• If the .Prepare() should be called before sending the request out, we should probably make a note in the README.md
• Unrelated to this PR: move the example into a go file and add the link to it in the readme (eventually adding the prepare method if necessary)