Update documentation regarding building ISO

We have a lot of changes that should be reflected in
building ISO documentation

Change-Id: I7226d5fb04c8528a09070f917d9feaad6d7199cd
Related-bug: #1517958

docs/buildsystem.rst

@@ -11,10 +11,7 @@ This repository contains a set of GNU Make build scripts.
 Quick start
 -----------
 
-1. You must use one of the following distributions to build Fuel components or the build process may fail. Note that build only works for x64 platforms.
+1. You must use Ubuntu 14.04 distribution to build Fuel components or the build process may fail. Note that build only works for x64 platforms.
-
-* Ubuntu 12.04
-* Ubuntu 14.04
 
 2. Check whether you have git installed in
    your system. To do that, use the following command:
@@ -85,7 +82,7 @@ Build system structure
 Fuel consists of several components such as web interface,
 puppet modules, orchestration components, testing components.
 Source code of all those components is split into multiple git
-repositories like:
+repositories like, for example:
 
 - https://github.com/openstack/fuel-web
 - https://github.com/openstack/fuel-astute
@@ -130,10 +127,6 @@ pieces of Fuel build system:
   ones which are to be copied on Fuel ISO even if Internet
   connection is down.
 
-* **puppet** - contains the code used
-  to pack Fuel puppet modules into a tarball that is afterwards
-  put on Fuel ISO.
-
 * **packages** - contains DEB and RPM
   specs as well as make code for building those packages,
   included in Fuel DEB and RPM mirrors.
@@ -141,16 +134,9 @@ pieces of Fuel build system:
 * **bootstrap** -  contains a make script intended
   to build CentOS-based miniroot image (a.k.a initrd or initramfs).
 
-* **image** - contains **make** scripts for building CentOS
-  and Ubuntu images using the Fuel mirrors, built
-  from the scripts in the *mirror* directory. The images
-  are alternative to using the standard anaconda and debian installers.
-
 * **docker** - contains the make scripts to
   build docker containers, deployed on the Fuel Master node.
 
-* **upgrade** - contains make scripts for building Fuel upgrade tarball.
-
 * **iso** - contains **make** scripts for building Fuel ISO file.
 
 **Fuel-main** also contains a set of directories which are not directly
@@ -159,12 +145,6 @@ related to Fuel build processes:
 * **virtualbox** - contains a set of shell scripts
   which allow one to deploy Fuel demo lab easily using VirtualBox.
 
-* **utils** -  contains a set of utilities used for
-  maintaining Fuel components.
-
-* **fuelweb_test** and **fuelweb_ui_test** -  contain
-  the code of Fuel system tests.
-
 
 .. _build-targets:
 
@@ -187,11 +167,6 @@ Build targets
 * **iso** - used for building Fuel ISO. If build succeeds,
   ISO is put into build/artifacts folder.
 
-* **img** - used for building Fuel flash stick image,
-  binary copied to a flash stick. That
-  stick is then used as a bootable device and
-  contains Fuel ISO as well as some auxiliary boot files.
-
 * **clean** - removes build directory.
 
 * **deep_clean** - removes build directory and local mirror.
@@ -233,12 +208,6 @@ They are defined in **config.mk** file:
   just ISO name.
   By default, it is **$(ARTS_DIR)/$(ISO_NAME).iso**.
 
-* **UPGRADE_TARBALL_NAME** - defines the name of upgrade tarball.
-  By default, it is **$(UPGRADE_TARBALL_NAME).tar**.
-
-* **UPGRADE_TARBALL_PATH** - used to define full upgrade tarball path.
-  By default, it is **$(ARTS_DIR)/$(UPGRADE_TARBALL_NAME).tar**.
-
 * **VBOX_SCRIPTS_NAME** - defines the name of the archive with
   VirtualBox scripts.
   By default, it is placed into **$(VBOX_SCRIPTS_NAME).zip**.
@@ -270,8 +239,6 @@ They are defined in **config.mk** file:
 Other options
 -------------
 
-* **BUILD_OPENSTACK_PACKAGES** - list of Openstack packages to be rebuilt from source.
-
 * **[repo]_REPO** - remote source code repo.
   URL or git repository can be specified for each of the Fuel components.
   (FUELLIB, NAILGUN, ASTUTE, OSTF).
@@ -310,19 +277,4 @@ Other options
   For example,
   *qemu2,http://osci-obs.vm.mirantis.net:82/centos-fuel-5.1-stable-15943/centos/ libvirt,http://osci-obs.vm.mirantis.net:82/centos-fuel-5.1-stable-17019/centos/*.
 
-* **EXTRA_DEP_REPOS** - extra repos with DEB packages.
+Note that if you want to add more packages to the Fuel Master node, you should update the **requirements-rpm.txt** file.
-  Each repo must consist of an url,
-  distro and section parts.
-  Repos must be separated by bar:
-  <first_repo_path>|<second_repo_path>
-  For example,
-  *http://fuel-repository.mirantis.com/repos/ubuntu-fuel-5.1-stable-15955/ubuntu/|http://fuel-repository.mirantis.com/repos/ubuntu-fuel-5.1-stable-15953/ubuntu/*.
-
-** **FEATURE_GROUPS** - options for the ISO.
-  Combination of the following:
-
-  * mirantis (use mirantis logos and logic)
-
-  * experimental (allow experimental features on Fuel web UI)
-
-Note that if you want to add more packages to the Fuel Master node, you should update the **requirements-rpm.txt** and the **requirements-deb.txt** files.