Respect EXECUTABLE_OUTPUT_PATH when set

This is a small change to make the toolchain obey the
EXECUTABLE_OUTPUT_PATH CMake variable when set by the
user. This variable is a CMake convention and documented
here: http://www.cmake.org/Wiki/CMake_Useful_Variables
Also respect EXECUTABLE_OUTPUT_PATH for uploads.
Merge pull request #5 from mikepurvis/respect-output-path

Respect output path