overhaul of code structure and fixed spherical harmonics issue. Now the package requires installation and C++ boost math 1.48
speed optimization, 35% faster
wrapped spherical bessel j from boost which is one digit more precise than scipy. cleaned up redundant definitions of spherical harmonics and spherical bessel
Merge branch 'master' of https://github.com/jeffzhen/simulate_visibilities
add compare_beam_spherical_harmonics.py to compare the error of different nside