Add read-only memory component

[kelsey-sorrels]

The read-only memory component has a variable address width and 4,8,16,
or 32 bit data width. The data is specified as a string of hexadecimal
characters. Whitespace is ignored.

The user-supplied hex characters are converted into an Array of values
when the component is created or edited. To decide the state of the
output values, the input values are used to computer an array index. The
index is used to look up the value in the array. Finally the value is
sent to the outputs.

[GGBRW]

Hi! First of all, I am so sorry for the late response.
Me and a friend have made this application initially for just a high school project. We hadn't much programming experience which is why the code of BOOLR is an unorganized mess (So lots of respect for being able to create such a good pull request! ;).) Later we found out that there were a lot of people interested in using BOOLR and that it could be used for education.
We have plans for lots and lots of useful features and improvements for making BOOLR a perfect piece of software, but the current version for BOOLR is just not stable and organized enough for extending it with those features. That's why we have started working on a second version of BOOLR, from scratch.
Currently the repo for BOOLR2 is private, but we are still discussing with our university for making it public.
For that reason this repo won't be active anymore, but thank you really much for taking the effort for making this PR. It will definitly be included in BOOLR2! I'll let you know if the BOOLR2 repo will be public.