Minor fixes to README.md files

* If a dedicated publication/publisher option (e.g., IEEE, ACM, LNCS)
  is provided, do not overwrite publisher attribute. This allows to
  specify a different publisher if needed. This can, e.g., be use
  to specify a society of IEEE:

  \usepackage[IEEE,publisher={IEEE Computer Society}, ...]{authorarchive}

* Changed the default publisher for the IEEE option from "IEEE Computer
  Society" to "IEEE". Please use the publisher-option if you want to
  specify a society.

Closes: https://github.com/adbrucker/authorarchive/issues/12

* If a dedicated publication/publisher option (e.g., IEEE, ACM, LNCS)
  is provided, do not overwrite publisher attribute. This allows to
  specify a different publisher if needed. This can, e.g., be use
  to specify a society of IEEE:

  \usepackage[IEEE,publisher={IEEE Computer Society}, ...]{authorarchive}

* Changed the default publisher for the IEEE option from "IEEE Computer
  Society" to "IEEE". Please use the publisher-option if you want to
  specify a society.

Closes: https://github.com/adbrucker/authorarchive/issues/12

ranges in the self archiving text.

Fixes: https://github.com/adbrucker/authorarchive/issues/10