Moved roundup-tracker.org infrastructure docs to website/README.txt This change makes developers.txt as the place for people contributing to the code base and README.txt to those maintaining the infrastructure. The old state was website/README.txt had reference to doc/developers.txt for updating issues.roundup-tracker.org. Removed reference and move docs to website/README.txt. doc/developers.txt had a section on updating website and wiki that referenced website/README.txt. Removed section, replaced with sentence that references website/README.txt for all infrastructure.

<!--
 This is the default body that is displayed when people visit the
 tracker. The tag below lists the currently open issues. You may
 replace it with a greeting message, or a different list of issues or
 whatever. It's a good idea to have the issues on the front page though
-->
<span tal:replace="structure python:db.issue.renderWith('index',
    sort=[('-', 'activity')], filter=['status'],
    columns=['activity','title','creator'],
    filterspec={'status':['1','2','4']})" />