Add LoKi dE/dx functors from 2018-patches

Add the same LoKi functors previously added to 2018-patches (!956 (merged), !1065 (merged)) to run2-patches as well.

The code was transfered with only the following changes:

• Switch to newer cmake files
• Change loading test to pytest
• Remove UNLIKELY
• Change default value of TRTIME to be -1000 and not nan, which would have been the default for the corresponding tool in run2-patches.
• Add DEDXPID functor, which was previously merged to 2018-patches (!1066 (merged))