[FIX] as discussed in #822
[FIX] simplify code, as discussed in #822
[FIX] fix bug, as discussed in #822
[FIX] remove dead code, as discussed in #822
[FIX] sane input validation for CompressedInputSource
[FIX] remember whether RT was set or not
[FIX] at least initialized all members, in the proper order
[FIX] fix sorting for quantile computation
[API,INTERNAL] peak boundary structures added, Eigen splines replaced by CubicSplines2d
[TEST] class tests fixed
[TEST] TOPP tests fixed
[TEST] test for peak boundaries added
Merge pull request #846 from hroest/fix/fixesFrom822

Fix/fixes from822
Merge remote-tracking branch 'upstream/develop' into feature/PeakPickerHiRes_boundaries
Merge pull request #847 from lars20070/feature/PeakPickerHiRes_boundaries

peak boundaries and new cubic splines for PeakPickerHiRes
[FIX] fix windows compile error

- windows complains about "redefinition; different linkage" which should
  be fixed if declaration and definition match.
Merge pull request #852 from hroest/fix/WindowsFix

[FIX] fix windows compile error (redefinition; different linkage)