docs: refresh & structure overhaul

Rework the doc in order to improve the navigation experience and to make
it easier to update the doc:

- simplify structure: docs/{release-notes,user,developer}
- recreate sphinx config file
- switch theme from opnfv to piccolo
- fix minor rst issues
- fix external references
- add missing license headers (add a short header with copyright and
  SPDX license identifier to the files lacking the information.  The
  header is based on https://github.com/david-a-wheeler/spdx-tutorial)

Change-Id: I9a1135a2873d9955beb26760e0cb6c5d6c1326bd
Signed-off-by: Gwenael Lambrouin <gwenael.lambrouin@orange.com>

1 files changed, 0 insertions, 26 deletions

diff --git a/docs/development/overview/overview.rst b/docs/development/overview/overview.rst
deleted file mode 100644
index 26e19d1..0000000
--- a/docs/development/overview/overview.rst
+++ /dev/null
@@ -1,26 +0,0 @@
-.. This work is licensed under a Creative Commons Attribution 4.0 International
-.. License.
-.. http://creativecommons.org/licenses/by/4.0
-.. (c) Cisco Systems, Inc
-
-.. contents::
-   :depth: 3
-   :local:
-
-Introduction
-----------------
-NFVbench is a python application that is designed to run in a compact and portable format inside a container and on production pods.
-As such it only uses open sourec software with minimal hardware requirements (just a NIC card that is DPDK compatible).
-Traffic generation is handled by TRex on 2 physical ports (2x10G or higher) forming traffic loops up to VNF level and following
-a path that is common to all NFV applications: external source to top of rack switch(es) to compute node(s) to vswitch (if applicable)
-to VNF(s) and back.
-
-Configuration of benchmarks is through a yaml configuraton file and command line arguments.
-
-Results are available in different formats:
-- text output with tabular results
-- json result in file or in REST reply (most detailed)
-
-Logging is available in a log file.
-
-Benchmark results and logs can be optionally sent to one or more remote fluentd aggeregators using json format.