docs: better docs, mv doxygen to sphinx

This patch refactors the VPP sphinx docs
in order to make it easier to consume
for external readers as well as VPP developers.

It also makes sphinx the single source
of documentation, which simplifies maintenance
and operation.

Most important updates are:

- reformat the existing documentation as rst
- split RELEASE.md and move it into separate rst files
- remove section 'events'
- remove section 'archive'
- remove section 'related projects'
- remove section 'feature by release'
- remove section 'Various links'
- make (Configuration reference, CLI docs,
  developer docs) top level items in the list
- move 'Use Cases' as part of 'About VPP'
- move 'Troubleshooting' as part of 'Getting Started'
- move test framework docs into 'Developer Documentation'
- add a 'Contributing' section for gerrit,
  docs and other contributer related infos
- deprecate doxygen and test-docs targets
- redirect the "make doxygen" target to "make docs"

Type: refactor

Change-Id: I552a5645d5b7964d547f99b1336e2ac24e7c209f
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/docs/aboutvpp/hoststack.rst b/docs/aboutvpp/hoststack.rst
new file mode 100644
index 00000000000..b50c715a888
--- /dev/null
+++ b/docs/aboutvpp/hoststack.rst
@@ -0,0 +1,26 @@
+.. _hoststack:
+
+==========
+Host Stack
+==========
+
+VPP’s host stack leverages VPP’s graph based forwarding model and vectorized packet
+processing to ensure high throughput and scale transport protocol termination. It
+exposes apis that apart from allowing for efficient user-space app consumption and
+generation of data, also enables highly efficient local inter-app communication.
+
+At a high level VPP’s host stack consists of 3 major components:
+
+* A session layer that facilitates interaction between transport protocols and applications
+* Pluggable transport protocols, including TCP, QUIC, TLS, UDP
+* VCL (VPPComs library) a set of libraries meant to ease the consumability of the stack from application perspective
+
+All of these components were custom built to fit within VPP’s architecture and to
+leverage its speed. As a result, a significant amount of effort was invested into:
+
+*  building a transport pluggable session layer that abstracts the interaction between applications and transports using a custom-built shared memory infrastructure. Notably, this also allows for transport protocols that are typically implemented in applications, like QUIC and TLS, to be implemented within VPP.
+* a clean slate TCP implementation that supports vectorized packet processing and follows VPP’s highly scalable threading model. The implementation is RFC compliant, supports a high number of high-speed TCP protocol features and it was validated using Defensic’s Codenomicon 1M+ tests suite.
+* VCL, a library that emulates traditional asynchronous communication functions in user-space, all while allowing for new patterns to be developed, if needed.
+* implementing a high performance “cut-through” communication mode that enables applications attached to vpp to transparently exchange data over shared memory without incurring the extra cost of a traditional transport protocol. Testing has shown this to be much more efficient than traditional inter-container networking.
+
+For developer features press next.