Add Support For PIC 16F877

I've added chipset data for the 16F877 that someone else may find useful. 

I've had one of these lying around for years not doing anything, but now I can actually make use of it!

As a side note I have a [develop branch](https://github.com/alchemycs/ardpicprog/tree/develop) in my fork that fixes up your reference to `Plang` to `ardpicprog` as well as some notes on the 16f877 and the current draw. I left them out of this pull request in case you wanted to deal with it some other way.

Also I wanted to say thanks for the work you have done on this project!