Handle empty upload

make edits in README.md

QR code, html5 player

ISSUE-44 delete support

ISSUE-131 fix mistake with request max memory

GA/UserVoice opt-in

ISSUE-92 added http basic auth handler for upload

refactor bash script without temp files

Timeout reader wrapper actually prevents big upload

ISSUE-109 fragment and query separators not escaped

Update README.md

Add "Windows support" to README

Run standard gofmt command on project root.

- go version go1.10.3 darwin/amd64

Signed-off-by: ia <isaac.ardis@gmail.com>

* GDrive provider support
* More reliable basedir ownership
* Fix mimetype

MAINTAINER is deprecated, using LABEL now

Added a section that explains how to get the `transfer` alias on Windows.

Implement support for custom s3 endpoints

Switch to alpine base image

This drastically decreases the overall image size. Quick comparison:

```
# Image fetched from Docker Hub
dutchcoders/transfer.sh   latest              a875ed5dfa56        5 months ago        704MB
# Image just built
dutchcoders/transfer.sh   latest              a220c49297eb        4 minutes ago       269MB
```

- support for max downloads
- support for expiring downloads