Latest improvements to 'isorespin.sh'

Ever wondered whether you are running the latest version of 'isorespin.sh'? I've now added a '--check' option that does exactly that. Starting with version 8.1.4 when you check and you are on the latest version you will get a message similar to:

linuxium@LINUXIUMONE:~$ isorespin.sh --check
/usr/local/bin/isorespin.sh: Version: 8.1.4 is the latest version.
linuxium@LINUXIUMONE:~$ 

otherwise you will get a message similar to:

linuxium@LINUXIUMONE:~$ ./isorespin.sh --check
./isorespin.sh: Version: 8.1.3 should be upgraded as 8.1.4 is the latest version.
linuxium@LINUXIUMONE:~$ 

indicating that you should download the latest version from 'isorespin.sh'.

I've also added some additional checks to prevent common issues that have previously been reported.

Firstly you cannot respin an ISO on an OS that doesn't support 'systemd' if you want to use either the '--apollo' or the '-b Linuxium' options. Also you cannot respin an ISO if it doesn't support 'systemd' when using the '--atom', '--apollo' or '-b Linuxium' options:

linuxium@LINUXIUMONE:~$ isorespin.sh -i ubuntu-14.04.5-desktop-amd64.iso --atom
Extracting ISO ...
Parallel unsquashfs: Using 4 processors
166333 inodes (175651 blocks) to write

[===========================================================/] 175651/175651 100%

created 105294 files
created 16104 directories
created 60921 symlinks
created 82 devices
created 0 fifos
/usr/local/bin/isorespin.sh: The '--atom' option is only compatible with an ISO that uses 'systemd'.
linuxium@LINUXIUMONE:~$ 

Secondly you cannot respin an ISO that is EOL (End Of Life):

linuxium@LINUXIUMONE:~$ isorespin.sh -i ubuntu-17.04-desktop-amd64.iso --atom
Extracting ISO ...
/usr/local/bin/isorespin.sh: ISO is EOL.
linuxium@LINUXIUMONE:~$ 

Finally you cannot run the script on a 32-bit OS:

linuxium@LINUXIUMONE:~$ isorespin.sh -i ubuntu-17.10.1-desktop-amd64.iso --apollo
/usr/local/bin/isorespin.sh: This script can only be run on a 64-bit (amd64 or x86_64) OS.
linuxium@LINUXIUMONE:~$

Please donate if you find the script useful using the following link http://goo.gl/nXWSGf.