Remove rhel6 and py26 support

el6 is shipped with Python 2.6.x which is not expected
to be supported with the openstack kilo release.

For el6 support we need to do lot of thing differently,
which makes the code more complicated.

This change removes el6 and py26 support from devstack.

This change also removed a discontinued (1 year ago)
openSUSE 12.2 code path, which used a similar codepath as el6.

Several comment related to el6 also removed or modified.

Change-Id: Iea0b0c98a5e11fd85bb5e93c099f740fe05d2f3a

lib/databases/mysql

@@ -17,11 +17,7 @@ register_database mysql
 # Linux distros, thank you for being incredibly consistent
 MYSQL=mysql
 if is_fedora; then
-    if [[ $DISTRO =~ (rhel6) ]]; then
-        MYSQL=mysqld
-    else
-        MYSQL=mariadb
-    fi
+    MYSQL=mariadb
 fi
 
 # Functions
@@ -38,15 +34,9 @@ function cleanup_database_mysql {
         sudo rm -rf /etc/mysql
         return
     elif is_fedora; then
-        if [[ $DISTRO =~ (rhel6) ]]; then
-            stop_service mysqld
-            uninstall_package mysql-server
-            sudo rm -rf /var/lib/mysql
-        else
-            stop_service mariadb
-            uninstall_package mariadb-server
-            sudo rm -rf /var/lib/mysql
-        fi
+        stop_service mariadb
+        uninstall_package mariadb-server
+        sudo rm -rf /var/lib/mysql
     elif is_suse; then
         stop_service mysql
         uninstall_package mysql-community-server
@@ -70,11 +60,7 @@ function configure_database_mysql {
         my_conf=/etc/mysql/my.cnf
         mysql=mysql
     elif is_fedora; then
-        if [[ $DISTRO =~ (rhel6) ]]; then
-            mysql=mysqld
-        else
-            mysql=mariadb
-        fi
+        mysql=mariadb
         my_conf=/etc/my.cnf
     elif is_suse; then
         my_conf=/etc/my.cnf
@@ -110,7 +96,7 @@ function configure_database_mysql {
 
     if [[ "$DATABASE_QUERY_LOGGING" == "True" ]]; then
         echo_summary "Enabling MySQL query logging"
-        if is_fedora && ! [[ $DISTRO =~ (rhel6) ]]; then
+        if is_fedora; then
             slow_log=/var/log/mariadb/mariadb-slow.log
         else
             slow_log=/var/log/mysql/mysql-slow.log
@@ -158,11 +144,7 @@ EOF
     fi
     # Install mysql-server
     if is_fedora; then
-        if [[ $DISTRO =~ (rhel6) ]]; then
-            install_package mysql-server
-        else
-            install_package mariadb-server
-        fi
+        install_package mariadb-server
     elif is_ubuntu; then
         install_package mysql-server
     elif is_suse; then

lib/databases/postgresql

@@ -49,11 +49,7 @@ function configure_database_postgresql {
         pg_hba=/var/lib/pgsql/data/pg_hba.conf
         pg_conf=/var/lib/pgsql/data/postgresql.conf
         if ! sudo [ -e $pg_hba ]; then
-            if ! [[ $DISTRO =~ (rhel6) ]]; then
-                sudo postgresql-setup initdb
-            else
-                sudo service postgresql initdb
-            fi
+            sudo postgresql-setup initdb
         fi
     elif is_ubuntu; then
         pg_dir=`find /etc/postgresql -name pg_hba.conf|xargs dirname`