Add random-insertion flag to random-plush-genome
Add random-insertion flag to random-plush-genome

This does not break anything in random.clj, but it most assuredly breaks
code elsewhere. WARNING: The breaking changes are probably not compiler
errors and may show up in strange ways.

thelmuth/Clojush,lspector/Clojush,NicMcPhee/Clojush,NicMcPhee/Clojush,thelmuth/Clojush,saulshanabrook/Clojush,lspector/Clojush,Vaguery/Clojush,Vaguery/Clojush,saulshanabrook/Clojush