[TEST] add test for TraML file

- TraMLFile should be able to store a (valid) minimal example of a TraML
  file and read it again.
[API,INTERNAL] replace linear fit by B-spline in peak width estimation
[INTERNAL] B-spline wavelength adjusted
[FEATURE,API] removed template argument from FeatureMap
[INTERNAL] moved FeatureMap code to cpp file
[INTERNAL] moved ConversionHelper code to cpp file
[INTERNAL] moved FileHandler code to cpp file
[INTERNAL] moved IDMapper code to cpp file
[INTERNAL] moved TOPPBase code to cpp file
[FIX] added missing export macros and moved some more code from headers to cpp
[FIX] ensure valid TraML file is written by not outputting a double equal to numeric limits
[FIX,PYOPENMS] add operators to TargetedExperiment
[FIX] add inequality operator
pxd files
[NOP] rearrange pychecker ignore
[TEST,PYOPENMS] add test
[API,INTERNAL] new implementation of PeakWidthEstimator
[FIX] improve set_peaks documentation

- write message what went wrong in assertion code
- fix typo
- reserve space for new data (for speed)
[API] removes PeakWidthEstimator_ from MultiplexClustering
[TEST] PeakWidthEstimator class test added