Include all available imagery layers

[astrofrog]

There's no real reason to keep the initial restriction of having only top-level surveys in the available imagery layers, so this is a small fix to make sure we expose all of them:

In [5]: wwt.available_layers                                                                                                                           
Out[5]: 
['2MASS: Catalog (Synthetic, Near Infrared)',
 '2MASS: Two Micron All Sky Survey (Synthetic, Near Infrared)',
 '2Mass: Imagery (Infrared)',
 'Big Picture (Optical)',
 'Black Sky Background',
 'Bonn 1420 MHz Survey (Radio)',
 'CGRO Compton Telescope: 3 channel data (Gamma)',
 'COBE DIRBE (Infrared)',
 'COBE DIRBE Annual Average Map (Infrared)',
 'COBE DIRBE Zodi-Subtracted Mission Average (Infrared)',
 'Digitized Sky Survey (Color)',
 'EGRET Hard (Gamma)',
 'EGRET Soft (Gamma)',
 'EUVE 171 : Extreme Ultraviolet Explorer 171 Angstroms',
 'EUVE 405 : Extreme Ultraviolet Explorer 405 Angstroms',
 'EUVE 555 : Extreme Ultraviolet Explorer 555 Angstroms',
 'EUVE 83 : Extreme Ultraviolet Explorer 83 Angstroms',
 'Extreme Ultraviolet Explorer',
 'Fermi (Gamma)',
 'Fermi LAT 8-year (gamma)',
 'Fermi Six Months (Gamma)',
 'Fermi Year Three (Gamma)',
 'Fermi Year Two (Gamma)',
 'GALEX (Ultraviolet)',
 'GALEX 2 Combined',
 'GALEX 2 Far-UV',
 'GALEX 2 Near-UV',
 'GALEX 4 Far-UV',
 'GALEX 4 Near-UV',
 'GLIMPSE 360',
 'GLIMPSE/MIPSGAL',
 'GRANAT/SIGMA Flux (X-Ray)',
 'GRANAT/SIGMA Significance (X-Ray)',
 'HI All-Sky Continuum Survey (Radio)',
 'Hydrogen Alpha Full Sky Map',
 'IRIS 100 Microns (Infrared)',
 'IRIS 12 Microns (Infrared)',
 'IRIS 25 Microns (Infrared)',
 'IRIS 60 Microns (Infrared)',
 'IRIS: Improved Reprocessing of IRAS Survey (Infrared)',
 'NVSS: NRAO VLA Sky Survey (Radio)',
 'Planck CMB',
 'Planck Dust & Gas',
 'Planck Ionized Gas (free-free)',
 'Planck Lensing (Mass)',
 'Planck Molecular Gas (CO)',
 'Planck Spinning Dust',
 'Planck Synchrotron (non-thermal)',
 'Planck Thermal Dust',
 'RASS: ROSAT All Sky Survey (X-ray)',
 'ROSAT Broad Band Count Map (X-Ray)',
 'ROSAT Hard Band Count Map (X-Ray)',
 'ROSAT Hard Band Intensity (X-Ray)',
 'ROSAT PSPC summed pointed observations, 2 degree cutoff, intensity (X-Ray)',
 'ROSAT Soft Band Count Map (X-Ray)',
 'ROSAT Soft Band Intensity (X-Ray)',
 'SDSS: Sloan Digital Sky Survey (Optical)',
 'SFD 100 Micron (Infrared)',
 'SFD Dust Map (Infrared)',
 'SUMSS: Sydney University Molonglo Sky Survey (Radio)',
 'Swift BAT All-Sky Survey: Flux 14-195 keV (X-Ray)',
 'Swift BAT All-Sky Survey: Significance 14-195 keV (X-Ray)',
 'Tycho (Synthetic, Optical)',
 'USNOB: US Naval Observatory B 1.0 (Synthetic, Optical)',
 'VLA FIRST: Faint Images of the Radio Sky at Twenty-centimeters',
 'VLSS: VLA Low-frequency Sky Survey (Radio)',
 'WISE All Sky (Infrared)',
 'WMAP Cosmic Microwave Background',
 'WMAP ILC 5-Year CMB',
 'WMAP ILC 5-Year Cosmic Microwave Background',
 'WMAP K (Linear) 23 GHz',
 'WMAP K (Non-linear) 23 GHz',
 'WMAP K (Polarization Map) 50 uK',
 'WMAP K Band (Microwave)',
 'WMAP Ka (Linear) 33 GHz',
 'WMAP Ka (Non-linear) 33 GHz',
 'WMAP Ka (Polarization Map) 35 uK',
 'WMAP Ka Band (Microwave)',
 'WMAP Q (Linear) 41 GHz',
 'WMAP Q (Non-linear) 41 GHz',
 'WMAP Q (Polarization Map) 35 uK',
 'WMAP Q Band (Microwave)',
 'WMAP QVW Linear (Microwave)',
 'WMAP QVW Power (Microwave)',
 'WMAP V (Linear) 61 GHz',
 'WMAP V (Non-linear) 61 GHz',
 'WMAP V (Polarization Map) 35 uK',
 'WMAP V Band (Microwave)',
 'WMAP W (Linear) 94 GHz',
 'WMAP W (Non-linear) 94 GHz',
 'WMAP W (Polarization Map) 35 uK',
 'WMAP W Band (Microwave)',
 'Westerbork Northern Sky Survey (Radio)']

I've put this under 0.6.2 since I view this as a bug that we aren't currently exposing all the layers, and I'd forgotten we had placed that initial restriction.

[codecov]

Codecov Report

Merging #220 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master    #220   +/-   ##
======================================
  Coverage    56.5%   56.5%           
======================================
  Files          24      24           
  Lines        1745    1745           
======================================
  Hits          986     986           
  Misses        759     759

Impacted Files	Coverage Δ
pywwt/imagery.py	93.02% <100%> (ø)	⬆️

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[pkgw]

Well, that was straightforward!