reading HS2 pwr file header containing gradients

add method to write out all tags from master file into an Excel sheet.

this is used to avoid wine/HAWC2 locking 2 instead 1 thread per sim

Note that this illustrates that a documented and consistent tag
standard naming scheme is long overdue!

Update dlctemplate.py: removed outdated nn_blr=opt.nn_blr, nn_twt=opt.nn_twt. The template was not working!

also restore functionality of the deprecated function.

this issue was introduced by commit #cf15be69