Move the logger in a submodule

A lot of changes here, but it is mostly a big git rm -rf logger. The submodule is now hosted here https://gitlab.cosma.dur.ac.uk/lhausammann/csds-reader

The interesting changes are:

• Adding a submodule called CSDS
• autogen.sh is now updating the submodules (it is required due to the way AC_CONFIG_FILES is working)
• When running ./configure --enable-csds, I am also updating the submodule to be safe
• I am adding an old script from Peter to update the submodules

Due to the changes in the structure, some scripts for the logger might be broken now. As I am planning to rename everything, I will test and fix everything once the renaming is done.