docs: fix requirements funcparserlib (#1703)
docs: fix requirements funcparserlib (#1703)

* docs: fix requirements funcparserlib

* docs: fix blockdiag dependency on funcparserlib 2to3 deprecation on setuptools
dpgaspar/Flask-AppBuilder,dpgaspar/Flask-AppBuilder,dpgaspar/Flask-AppBuilder,dpgaspar/Flask-AppBuilder