Try to simplify and clean up files

[rgleason]

SteveAd and I would like to "clean up" some of these directories and old files that are hanging around unused and unwanted. Here is a file which reviews the files and directories and make some suggestions about cleanup. There are several folders that may or may not be needed dependent on whether the json-validation for odapi.h is done.

1. extinclude
2. extsrc
3. ocpninclude
4. ocpnsrc

I don't know what to do with these yet. Also there are an extraordinary number of:

• json, wxjson, etc. so many I don't know what to do with them all, but some work and some don't and some don't do anything.
• GL, GLES2, in different places, (perhaps not quite so bad in watchdog)
• Now with the addition of Dave's libs/PluginDC which has which has TexFont, pi_shaders, pidc, qtstylesheet cpp and h and builds as a lib and is specifically for Android I believe, perhaps some of this other stuff can be removed???

It would be helpful to have some review and reinforcement of this plan to remove some of these files or to put them in an OLD folder. File-summary.txt

[rgleason]

In addition to the changes suggested in "File-summary.txt"

1. I would like to remove the wx_config.bat in the root watchdog_pi directory because I have used that batch code in "bld.bat" and there is also the same file under msvc (used by circleci to build remotely).
2. In watchdog_pi/cmake I would like to move FindtinyXML.cmake, FindGTK3.cmake and SimpleWxConfig.cmake into an OLD directory and see if it all builds ok.

[rgleason]

And preceding commits.

Make careful note of the changes needed for moving extinclude and extsrc into Libs as a library Refactor libs. cleanup #56 https://github.com/rgleason/watchdog_pi/pull/56

https://github.com/rgleason/watchdog_pi/commit/ca853f920e0944323d494d9c1cb2a090ebaec20d