Created for the original issue in JENKINS-19506

I run customtools-plugin together with android-emulator-plugin, and when jenkins launches tasks for android-emulator, they are launched without the default PATH varable.
This means that the shell scripts that start the emulator can't find common tools as dirname, file and so on.

Workaround is to add a custom tool that defines default paths too, but thats site-wide and when some nodes have other PATH's than other, i can only add the directories that exists on all nodes.