Fix to issue #72 - add Ubuntu and Centos choices (#73)

* POSIX sh empty value check compatibility - part 2

* added Ubuntu choice with minimal version check

install.sh

@@ -47,6 +47,7 @@ chmod +x $0
 os_check=$(lsb_release -is)
 real_os=$os_check
 check_major_release=$(lsb_release -rs | cut -d. -f1)
+check_codename=$(lsb_release -cs)
 
 os_unsupported () {
 	echo " Your Operating System appears to be: "
@@ -55,18 +56,18 @@ os_unsupported () {
 	exit 2;
 }
 
-if [ $os_check = 'Raspbian' ]; then
+os_debian_common () {
-	echo "${yellow}Detected Raspbian, using Debian for compatibility${normal}"
-	os_check="Debian"
-fi
-if [ $os_check = 'Debian' ]; then
-	if [ $check_major_release -ge 8 ]; then
 	verbose "Removing the CD image from /etc/apt/sources.list"
 	sed -i '/cdrom:/d' /etc/apt/sources.list
 	verbose "Updating system before starting."
 	apt-get update && apt-get -y upgrade
 	verbose "Installing Git"
 	apt-get install -y git
+}
+os_fetch_installer () {
+	if [ ! -d /usr/src ]; then
+		mkdir -vp /usr/src
+	fi
 	cd /usr/src
 	verbose "Fetching Installer"
 	if [ -d /usr/src/fusionpbx-install.sh ]; then
@@ -75,13 +76,42 @@ if [ $os_check = 'Debian' ]; then
 	else
 		git clone https://github.com/fusionpbx/fusionpbx-install.sh
 	fi
-		cd /usr/src/fusionpbx-install.sh/debian
+}
-		./install.sh $@
+
+if [ .$os_check = .'Raspbian' ]; then
+	echo "${yellow}Detected Raspbian, using Debian for compatibility${normal}"
+	os_check="Debian"
+fi
+if [ .$os_check = .'Ubuntu' ]; then
+	echo "${yellow}Detected Ubuntu, using Debian for compatibility${normal}"
+	os_check="Debian"
+fi
+if [ .$os_check = .'Debian' ]; then
+	if [ .$real_os = .'Debian' ]; then
+		echo "${yellow}Detected Debian${normal}"
+		if [ $check_major_release -ge 8 ]; then
+			os_debian_continue='true'
 		else
+			os_debian_continue='false'
 			error "Although you are running $real_os we require version >= 8"
 			os_unsupported
 		fi
+	fi
+	if [ .$real_os = .'Ubuntu' ]; then
+		if [ $check_major_release -ge 14 ]; then
+			os_debian_continue='true'
+		else
+			os_debian_continue='false'
+			error "Although you are running $real_os we require version >= 14"
+			os_unsupported
+		fi
+	fi
+	if [ .$os_debian_continue = .'true' ]; then
+		os_debian_common
+		os_fetch_installer
+		cd /usr/src/fusionpbx-install.sh/debian
+		./install.sh $@
+	fi
 else
 	os_unsupported
 fi
-