Support macros (parameters) in Start In directory

Originally created by: pckuj...@gmail.com

What steps will reproduce the problem?
1. Create/edit a command and put %curdir in the "Start In" field
2. Try to run the command

What is the expected output? What do you see instead?
I expected this to run the command in the current directory. Instead, the command wouldn't run. I think that the default might be to run the command in the current directory, but explicitly adding %curdir causes the command to fail silently. Instead, "Start In" should support the %xyz macros or else fail with a clear error.

What version of the product are you using? On what operating system?
1.8.4.847 on Win7 32bit