Add xAxisLables and showOrigin option

[L1cardo]

I didn't work with ChartData, because it is a [(String, Double)], and I don't think it is good for for in, so I created a xAxisLables model
I don't know if this is the proper way
Fix #37
Here is how to use it:

        LineView(data: [8, 23, 54, 32, 12, 37, 7, 23, 43],
                 xAxisLables: ["2020-12-4", "2020-12-5", "2020-12-6","2020-12-4", "2020-12-5", "2020-12-6","2020-12-4", "2020-12-5", "2020-12-6"],
                 title: "LineView",
                 legend: "Legend",
                 showOrigin: true,
                 valueSpecifier: "$ %.2f")

[L1cardo]

Also has a showOrigin option

[AppPear]

Hi, thanks for contributing. Sorry I didn't merge this PR, in the meantime so many PR and Issues piled up and the project was not very expandable and flexible I decided to go with a version 2.0 So until it's release I can't merge this request. I made the new planned release contribution friendly so if you'd like to check it out please got to #89

Thanks again!

[dadixon]

Will this get merged into version 2?