Octoprint-cli

**Features and Fixes**
* Moves connection/permission check to after loading if `colored` method to fix colored output for error message
* Checks for updates using GitHub API
* Added flags to `octoprint-cli files list` to filter out files or folders

**Features and Fixes**
* Move `termcolor` loading and formatted text setting to after configuration file loading in the program to fix the configuration setting

**Features and Fixes**
* Rewrite using `argparse` instead of `sys.argv` for easier expansion in the future
* Individual help pages for commands using `--help` or `-h`
* Use custom config file paths using `--config`

**Features and fixes**

* Printer G-code execution from terminal using the new `gcode` command
* File listing is now sorted alphabetically folders before files
* Typo fixes
* Code quality imporovements

This release fixes some issues in continuous mode and POST requests as well as supporting layer information from the OctoPrint-DisplayLayerProgress plugin API.

**Features and fixes**

* Add a layer command to get print layer information from OctoPrint-DisplayLayerProgress
* Add layer information from OctoPrint-DisplayLayerProgress to continuous output mode
* Switch requests POST requests from using `data` to `json` to stop 400 error
* Add output to Offline state in continuous

This release fixes some issues and introduces a new file uploading feature.

**Features and fixes**
* New `octoprint-cli files upload [file]` sub-command for uploading GCODE or STL files to the OctoPrint local folder
* Fix estimated total time and time left bug that occurs when the time is longer than a day
* Fix continuous mode breaking when printer offline and no ports are available