This commit adds a dedicated page for the Zephyr SDK under the
'Toolchains' sub-category under 'Developing with Zephyr'.
The content of this page is based on the Zephyr SDK installation
instruction from the 'Getting Started Guide'.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit adds the 'Toolchains' sub-category under the 'Developing
with Zephyr' category with toolchain-related documentations that were
previously located under the 'Getting Started Guide' sub-category.
It also reworks the toolchain-related documentation in the "Beyond
Getting Started Guide" document such that it is more up to date and any
confusing and/or misleading details are removed.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>