[FEATURE] improved purity computation
[FEATURE] adds puritystate struct to track current precursor and followup scan
[FIX] fixed some float compare warnings
[FEATURE,INTERNAL] added faster purity computation that works in a single linear scan
[INTERNAL] moved purity computation into separate method allowing computation on different spectra
[FIX,FEATRE] fixed computation of follow up scan and implemented purity computation based on Savitski et al. 2011

 * removed debug output
 * adapted test purity values, values where manually validated
[INTERNAL] code cleanup and some more documentation
[INTERNAL] improved handling of experiment end case
[INTERNAL,PARAM] purity interpolation can now be deactivated

 * fixed small bug in purity computation
[INTERNAL] added alternative implementation for purity computation
[INTERNAL] improved purity computation
[INTERNAL] replaced purity computation with new version
[TEST] added test with disabled purity interpolation
[NOP] uncrustify
[DOC] updates class doc of IsobaricChannelExtractor
escape percent sign to fix usage documentation
fix time resolution of seed initialization: was seconds, now microseconds
[INTERNAL] added fabs to avoid problems with negative RTs
Merge pull request #1057 from cbielow/doc/GenericWrapper

GenericWrapper doc has minor quirks
Merge pull request #1056 from cbielow/fix/UniqueIDGen-seedInit

[FIX] UniqueIdGenerator susceptible to identical RNG seeds