fix HPCBIOS easyblocks headers

Signed-off-by: Fotis Georgatos <fotis.georgatos@uni.lu>
improve headers and document Kenneth Hoste as co-author

Signed-off-by: Fotis Georgatos <fotis.georgatos@uni.lu>
Merge pull request #101 from fgeorgatos/fix_HPCBIOS_easyblocks_headers

fix headers of HPCBIOS related easyblocks