Warn users against creating files in "Program Files", at least on Windows

[Adam Winer]

This has generated errors for several users.

[Adam Winer]

Scythebill does warn about “Program Files”. But… it doesn’t warn about “Program Files (x86)”, which is where Scythebill actually (still) installs on Windows.

(It shouldn’t install there - Scythebill is 64-bit, so standard “Program Files” would be better. Just changing the installer to 64-bit would likely be the simplest resolution at this point.)

[Adam Winer]

The resolution of issue #411 makes this one a lot less important.

[Adam Winer]

This has generated errors for several users.