untangle the repository mess

qa & release related scripts are now distributed more or less arbitrarily over a number of repositories:

• qt/qtqa
• qt/qtrepotools
• qtqa/sysadmin
• qtqa/tqtc-coin-ci
• qtsdk/qtsdk
• qtsdk/tqtc-qtsdk

furthermore, these repos appear obsolete:

• qtqa/testconfig
  • unlike qtqa/tqtc-testconfig which is still in use
• further repos will be obsoleted as we move stuff into coin

this situation is unsustainable and severely impacts "outsider" (that includes myself) willingness to participate in related processes.

for starters, all obsolete scripts should be identified and deleted, to get an overview of what is still relevant.

subsequently, scripts should be grouped by purpose.