Custom function for generating a cross-platform compatible fmpurl for opening files and running scripts via the Open URL script step.

This file mostly exists due to this bug and my wanting to do cross-platform testing to confirm I can open/close files and run scripts via fmpurl.

fmpurl protocol facts

These facts were observed based on tests done by the fmpurl-protocol-tests file on multiple platforms/versions. These were only tested with the Open URL script step with the specified file in Documents directory.

1. Account and password cannot be urlencoded
2. Account cannot contain any special characters or text with accents, but a space is fine.
3. Password can only contain these special characters ,;:()$ (of the one's I tested, at least).
   • FM Go is the most restrictive; FM Pro accepted other special characters.
4. Password cannot contain text with accents.
5. The work-around for a bug in iOS 6, 7, and 8 (http://thefmkb.com/11358) will fail if the filename contains spaces (only tested on iOS 9 and 10).
6. Filename cannot be urlencoded.
7. Filename can contain text with accents, spaces, and special characters (I only tested @).
8. If a script name is urlencoded, it can contain any character (of the set tested, at least). Many characters don't even need to be urlencoded, but results will vary across platforms.
   • same applies to script parameter
   • same applies to variable values
9. Variable names were not tested since I never use spaces, special characters, or accents in my variable names.

Tests that should still be done

1. Re-login to an already open file.
2. Login as [Guest].
3. Login to account without password.
4. Resolve, or document failing tests in fmpurl.fmp12 file, when run from FMGo.