Originally suggested by @pke in #135

Currently react-native-blob-courier supports multipart file uploads only, but there are situations where it is desirable to send a file to the server as a raw HTTP body.

Proposed solution
Add a send(request:SendRequest) method to TypeScript code base, inspired by HttpClient.Send.

SendRequest would look something like:

interface SendRequest {
  method:string;
  absolutePath:string;
  headers:dictionary;
  returnResponse: boolean;
}

Progress

• Add send(request:SendRequest) method to TypeScript code base
• Add a send(method:string,absolutePath:string,headers:dictionary) method to Android code base
• Add a send(method:string,absolutePath:string,headers:dictionary) method to iOS code base
• Add TypeScript tests
• Add Android tests
• Add iOS tests