use build file to ensure python3.7

this seems to generally lead to an issue with conflicts between the julia and conda versions of mkl for this reason we uninstall numpy and install nomkl so that the python packages don’t try to install mkl

Author: mjohnson541

deps/build.jl

@@ -0,0 +1,12 @@
+using PyCall
+if PyCall.pyversion.major != 3 || PyCall.pyversion.minor != 7
+    using Conda
+    const Pkg = Base.require(Base.PkgId(Base.UUID("44cfe95a-1eb2-52ea-b672-e2afdf69b78f"), "Pkg"))
+    Conda.add("python=3.7")
+    Conda.rm("numpy") #get around MKL problem
+    Conda.add("nomkl")
+    Conda.add("numpy")
+    Conda.add_channel("rmg")
+    Conda.add("rmg")
+    Pkg.build("PyCall")
+end

src/ReactionMechanismSimulator.jl

@@ -1,11 +1,5 @@
 module ReactionMechanismSimulator
     using PyCall
-    if PyCall.pyversion.major != 3 || PyCall.pyversion.minor != 7
-        using Conda
-        using Pkg
-        Conda.add("python==3.7")
-        Pkg.build("PyCall")
-    end
     push!(PyVector(pyimport("sys")["path"]), "")
     const Chem = PyNULL()
     const molecule = PyNULL()