I'm looking for a software that can compare a bacterial clone with the reference genome to identify some changes in genome content (Deletion/insertion/substitution).
breseq can be a good option for you as bacterial genome is haploid. Check this paper https://bmcgenomics.biomedcentral.com/articles/10.1186/1471-2164-15-1039. However BBMap's callvariants.sh natively supports haploid genomes; the default ploidy is 1. It has been used for mutation study in E coli.
I used before GATK as Snijesh suggested but the analysis afterwards was a little unconvenient because the SNP calling was designed for eukaryotes. I do believe they've updated but i'm not sure. Or maybe now there is another tool for the variant filtering that can be used in this pipeline. Maybe R :p.
The advantage is that i found it quite user friendly because it had quite a lot of options superwell explained in the webpage.
Also, I heard about an R package called DEseq but i didn't use it myself.
GATK is optimized for diploid genome .If you want to use GATK you should use GATK with the updated version of haplotype caller which can now be set to ploidy =1. See the link for better understanding and how to use https://approachedinthelimit.wordpress.com/2015/10/09/variant-calling-with-gatk/. perhaps you can check this biostar page where similar problem has been discussed https://www.biostars.org/p/47860/
I find Sequencher from http://www.genecodes.com/ really user friendly. You can insert your own reference sequence and then compare the sequences by nucleic acid and manipulate the sequence (for ex. add insertions or deletions) to visualize the best possible alignment.