Measurement and Correlation of High-Pressure Densities and Atmospheric Viscosities of Ionic Liquids: 1Butyl-1-Methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide) 1Allyl-3-Methylimidazolium Bis(trifluoromethylsulfonyl)imide 1Ethyl-3-Methylimidazolium Tetracyanoborate, and 1-Hexyl-3-Methylimidazolium Tetracyanoborate