docs dirs per opnfv guidance

Change-Id: I4dff8fda6110a83ca759a626160f5cd6569514ea
Signed-off-by: Koren Lev <korenlev@gmail.com>

diff --git a/documentation/admin-guide.pdf b/docs/release/admin-guide.pdf
similarity index 100%
rename from documentation/admin-guide.pdf
rename to docs/release/admin-guide.pdf

diff --git a/documentation/install-guide.pdf b/docs/release/install-guide.pdf
similarity index 100%
rename from documentation/install-guide.pdf
rename to docs/release/install-guide.pdf

diff --git a/documentation/quick-start.pdf b/docs/release/quick-start.pdf
similarity index 100%
rename from documentation/quick-start.pdf
rename to docs/release/quick-start.pdf