Documentation improvements and Reorganization of doc / docs folder

[smlambert]

We created docs folder to update documentation underneath it, with the idea to remove doc folder eventually. This issue is to finish moving documents over and remove the doc folder.

https://github.com/adoptium/aqa-tests/blob/master/doc/pages/JenkinFeatures.md

• fix headings to all be same level (some are level2, some level3, look at the outline to see which need correction)
• https://github.com/adoptium/aqa-tests/blob/master/doc/pages/JenkinFeatures.md - update DYNAMIC_COMPILE to mention it is needed when running functional test group with JDK_IMPL hotspot and trying to compile the entire functional folder, otherwise TKG will try and compile openj9 test material (and compile will fail when using hotspot)

[Agaba-derrick]

@smlambert would like to give this a try

[smlambert]

Sure thing, thanks @Agaba-derrick !