Closes #19

Update documentation for the ECSS definitions

Group Services and ECSS Definitions into a doxygen page

Switch order of execution to improve performance

Fix the build

This marks completion of the arbitrary type field feature

Other changes: Add a couple more tests

Other changes:
Tweaked addNewParameter() in order for the IDs to be arbitrary (insertion
of already existing ID test incoming) according to suggestion by @kongr45gpen

Additional changes:
Fixed tests for parameter setting to accommodate the new way of parameter storage

Cause was an off-by-1 error in construction of the Parameter objects.
Minor changes to documentation

Also update some of the tests

Also update some of the tests

Looks like a test is breaking all of a sudden

Fixed names in ErrorHandler and enumeration of errors and removed explicit declaration of true or false in a CHECK

- changed variable names
- added breaks
- corrected a comment
- deleted explicit declaration of true/false in ifs
- fixed a bug in tests caused by passing the message by reference