change PlasMapper by cirdna EMBOSS

As commented in issue #3 (closed) , PlasMapper generates problems and can be replaced by cirdna, a program from EMBOSS.

The doc of cirdna is here.

I test it and see that commandline works fine without any prompt if I type:

cirdna -posblock Out -posticks Out -blocktype Outline -graphout  png -ruler Y -infile input.txt -goutfile test

These points are promising:

• GPLv3 licence
• easy to use/implement
• easy to install (sudo apt install emboss)
• simple are therefore robust

The dev work will be to parse blast output into the appropriate text format to be passed as cirdna input.