v1.0.5: Resolved backend bugs with the equation parser

• adjusted the call of the max/min functions: Use maxi and mini in the equations. Both functions take two input arguments, and return the larger/smaller one, respectively
• updated the PyRates reference in the readme and on the documentation website (using the PLOS CB paper now instead of the arxiv preprint)
• removed a bug where differential equations with a constant right-hand side were not properly handled by the automated compute graph optimization
• resolved an issue with the fortran backend where complex data types were not properly processed during the code generation