translation for register.tpl and code cleanup for print.tpl
Essentially taken from pvdl master
register.tpl: https://github.com/pvdl/simpleinvoices/commit/c8d516b9f47cd386e263a14891141b3675c1561f
print.tpl: 1 edit more than https://github.com/pvdl/simpleinvoices/commit/85f4f31b54c58fb01a553c22a91673f9e7909c9a