move nb.Noise's from noises.py into the relevant noise file

gwinc/ifo/Aplus/__init__.py

gwinc/ifo/CE1/__init__.py

gwinc/ifo/CE2silica/__init__.py

gwinc/ifo/CE2silicon/__init__.py

gwinc/ifo/Voyager/__init__.py

gwinc/ifo/aLIGO/__init__.py

gwinc/ifo/noises.py

gwinc/noise/coatingthermal.py

gwinc/noise/newtonian.py

gwinc/noise/quantum.py

gwinc/noise/residualgas.py

gwinc/noise/seismic.py

gwinc/noise/substratethermal.py

gwinc/noise/suspensionthermal.py