Add SSL CA integration support for Firefox Developer Edition

[h3xx]

This makes it easier to add more Firefox flavors to the list.

Also spruce up script:

• Don't do [[ -d ]], then mkdir -p -- just use mkdir -p (Unfortunately, OSX's install doesn't support -D)
• Add more messages about what it's doing.

[what-the-diff]

• The script now checks for Firefox and the Developer Edition of Firefox.
• If either is found, it will install a policies file to enable enterprise root certificates in that browser's profile directory (if one exists).
• It then installs the CA certificate into Mozilla's system-wide NSS database so all profiles can use it without having to import manually or via policy files.

[rangerz]

Is importing CA into Firefox still working for MacOSX ?

[h3xx]

Yes, I confirmed it's working to install the CA for both browsers, but I'd like someone else's input to test -- "Works on my machine"

The browsers still need to restart like they always have.