blackhole.py: original black hole attempt, solves for 1 point particle using Euler's method
blackhole_rk4.py: solves for 1 point particle using RK4 method
ke_pe_vs_mstar.py graphs the ke and pe of the system over time for a variable m_s
starball.py: main simulation method, solves for n=1000 particles using RK4 method and the Paczyński–Wiita potential
t_ellipse_vs_mbh.py determines the amount of time for the star to complete one ellipse around the black hole for a variable m_bh