Resolve "Replace inspect.getargspec references"

Closes #208

See merge request Monash/bilby!235

Allow prob to take in kwargs which are passed to product

See merge request Monash/bilby!248

This will help prevent conficts when other command-line interfaces are
invoked

Add __version__ module-level attribute

See merge request Monash/bilby!237

This reverts commit e577ba98

PriorSet -> PriorDict
BBHPriorSet -> BBHPriorDict
BNSPriorSet -> BNSPriorDict
CalibrationPriorSet -> CalibrationPriorDict

Introduced backports with deprecation warnings for the old classes

Resolve "clean=True doesn't work with Pymultinest"

Closes #190

See merge request Monash/bilby!232

Resolve "Redundant attribute assignment in WaveformGenerator.__init__"

Closes #211

See merge request Monash/bilby!238

add samplers to tests

See merge request Monash/bilby!236

Adds basic skymap/fits utilities

Closes #123

See merge request Monash/bilby!229

fix nburn and autocorr for ptemcee

See merge request Monash/bilby!234

update cpnest syntax

See merge request Monash/bilby!233

Update examples

See merge request Monash/bilby!228

# Conflicts:
#   examples/injection_examples/basic_tutorial.py
#   examples/injection_examples/binary_neutron_star_example.py