[devtools] Container image usage and s2i texts for all compiler toolsets

An ideal state for the compiler toolsets is to have sections for:

• using the container to compile code on system
• using the image with s2i
  This for all the 3 toolsets.

At the moment, there is only a section [1] on s2i usage for Go toolset which may serve as an inspiration / guide for the remaining 2 others.

For compiling code on system from the container, there is nothing.

These descriptions will be specific to our own packaging of the compilers (as the toolsets) and therefore cannot be substituted well by upstream docs.

[1] https://access.redhat.com/documentation/en-us/red_hat_developer_tools/2018.2/html/using_go_toolset/chap-image#sect-Image-Usage

[Not applicable since the linked issue is closed] UPD Jan 2020:
-[oss] also consider expanding toolsets installation chapters. Adding info about container image installation was suggested in -https://issues.redhat.com/browse/RHDEVDOCS-1123.--