Add the component drawing tool to fprime-community

[bocchino]

The component-drawing tool that we use (e.g., the one used to draw the component diagram for the LED Blinker tutorial) is based on the UNIX drawing tool pic. Due to concern that pic may be difficult for users to install and use, we have not included the component-drawing in the mainline F Prime code. Instead, we are looking to find or build a more modern and easy-to-use equivalent. In the mean time, though, since the pic-based tool is the best we have, we can add it to fprime-community so that users who wish to can use the tool.

[matt392code]

mermaid-fprime.md
Mermaid.js might be the best immediate replacement because:
Easy integration with existing documentation
No complex installation
Could be extended for F Prime specifics
Good for version control
Wide community support