Add `get_project_data()` to get project data from project 'id'

[statnmap]

https://github.com/toggl/toggl_api_docs/blob/master/chapters/projects.md#get-project-data

GET https://api.track.toggl.com/api/v8/projects/{project_id}

with successful response:

{
	"data": {
		"id":193838628,
		"wid":777,
		"cid":123397,
		"name":"An awesome project",
		"billable":false,
		"is_private":true,
		"active":true,
		"at":"2013-03-06T12:15:37+00:00",
		"template":true,
		"color": "5"
	}
}