Create env as a separate command

Author: astaric

scripts/windows/condainstall.bat

@@ -12,11 +12,15 @@ if not exist "%PREFIX%\python.exe" (
     rem # Create an empty initial skeleton to layout the conda, activate.bat
     rem # and other things needed to manage the environment. conda 4.1.*
     rem # requires at least one package name to succeed
+    "%CONDA%" create --yes  --quiet --prefix "%PREFIX%" ^
+        || exit /b !ERRORLEVEL!
+
     for %%f in ( vs*_runtime*.tar.bz2 ) do (
-        "%CONDA%" create --yes  --quiet --prefix "%PREFIX%" "%CD%\%%f" ^
+        "%CONDA%" install --yes --copy --quiet --prefix "%PREFIX%" "%CD%\%%f" ^
             || exit /b !ERRORLEVEL!
     )
 
+    echo Installing python into "%PREFIX%"
     rem # Also install python (msvc runtime and python might be required
     rem # for any post-link scripts).
     for %%f in ( python-*.tar.bz2 ) do (