EventLoaderEUDAQ2: rewrote and simplified how process_event() is called such that identical code blocks don't coexist

EventLoaderEUDAQ2: restructuring function process_event() and simplifying logic. process_tlu_event() can now be called from inside process_event()

Event.hpp: changed std::vector for trigger list to std::map and simplified the functions add_trigger() and has_trigger_id(), verified functionality by re-analysing run 190 -> I get the same number of TLU/Mimosa events in frame

EventLoaderEUDAQ2: rewrote the README to implement feedback, correct errors, improve on the explanation and fix multiple places where I used LaTeX syntax instead of markdown

Sorry, previous commit was not complete. Now I completely removed the old function increment_event_type_counters() and corrected setting the default values for the new parameters

EventLoaderEUDAQ2: removed function increment_event_type_counter() as it was replaced by std::map event_counts and event_counts_inframe

added std::map<> event_counts and event_counts_inframe as a more elegant and generic way than increment_event_type_counter. Kept the latter to confirm that both count equally. Will remove that function in the next commit.

Test of changing CMakeLists.txt to check if this solves the problem related to the missing library links when running corryvreckan. It doesn't solve the problem so this commit might be undone, but I don't like a dirty git repo

removing AnalysisTiming again which I accidentally committed yesterday --> this will be a separate merge request soon

changed type of trigger_ts in event class from uint64_t to double (default unit of corryvreckan is ns) and changed the EventLoaderEUDAQ2.cpp accordingly to match the types

changed usage of event->add_trigger_id to add_trigger according to last commit (change of event class), also added 1 histogram for event (frame) time - trigger time

changed Event.hpp: now we have a vector of std::pair{trigger_id, trigger_ts} such that later we can not only check for an existing trigger ID but also retrieve the corresponding time stamp, also added the corresponding function get_trigger_time()