Add tools/install_pip.sh

Install a known working recent version of pip that handles installation
dependencies more correctly than before.  Extract to a separate script
so it can be used apart from stack.sh.

* Install distro setuptools if it not already present
* Install pip from source tarball as get-pip.py proved to be unreliable
* Remove python-distribute and python-pip from all prereq files,
  move python-setuptools to 'general'
* Remove the earlier unfubar_setuptppls() call that attenpted to fix this
* Only update requirements.txt when no changes in repo

Tested on Precise, F18 and CentOS6.
* Fedora and RHEL allow pip to install packages ON TOP OF RPM-installed
  packages.  THIS IS BROKEN.  And is one reason we have to be so picky
  about order and so forth.

Change-Id: Ibb4b42119dc2e51577c77bbbbffb110863e5324d
diff --git a/files/rpms-suse/general b/files/rpms-suse/general
index f28267c..355af88 100644
--- a/files/rpms-suse/general
+++ b/files/rpms-suse/general
@@ -6,8 +6,8 @@
 openssh
 openssl
 psmisc
+python-setuptools # instead of python-distribute; dist:sle11sp2
 python-cmd2 # dist:opensuse-12.3
-python-pip
 python-pylint
 python-unittest2
 python-virtualenv
diff --git a/files/rpms-suse/keystone b/files/rpms-suse/keystone
index 7d9a7bf..403d82f 100644
--- a/files/rpms-suse/keystone
+++ b/files/rpms-suse/keystone
@@ -7,8 +7,6 @@
 python-SQLAlchemy
 python-WebOb
 python-devel
-python-distribute
-python-setuptools # instead of python-distribute; dist:sle11sp2
 python-greenlet
 python-lxml
 python-mysql
diff --git a/files/rpms-suse/ryu b/files/rpms-suse/ryu
index 90b43a4..3797b6c 100644
--- a/files/rpms-suse/ryu
+++ b/files/rpms-suse/ryu
@@ -1,5 +1,3 @@
-python-distribute
-python-setuptools # instead of python-distribute; dist:sle11sp2
 python-Sphinx
 python-gevent
 python-netifaces
diff --git a/files/rpms-suse/swift b/files/rpms-suse/swift
index db379bb..f3c95aa 100644
--- a/files/rpms-suse/swift
+++ b/files/rpms-suse/swift
@@ -6,8 +6,6 @@
 python-configobj
 python-coverage
 python-devel
-python-distribute
-python-setuptools # instead of python-distribute; dist:sle11sp2
 python-eventlet
 python-greenlet
 python-netifaces