Fixed error in finding Julia installation
Simulations in Julia are now ensured to stop at exact simulation times, which removes unexpected results created by numerical errors in the solver (using tstops argument in solve())
Removed automatic installation of Julia packages and instead wrote a separate function for this: install_julia_env(). install_julia_env() is called in .onLoad() ONLY if the custom environmental variable AUTO_INSTALL_JULIA_ENV is "true" and NOT_CRAN is "true". This is to ensure GitHub workflows have the Julia environment instantiated, but this will not affect users, as they do not have AUTO_INSTALL_JULIA_ENV.
Added vignette for formalizing Job Demands-Resources (JDR) Theory
Improved documentation
times to step, pulse, ramp, and seasonal