Commands with numeric arguments should accept type characters (s, d, b, f)

With the addition of Macros, we now have the ability to paste strings from JSON into commands. The problem is that sometimes some commands don't accept the string form of numeric JSON values.

For example, a double saved in JSON will always return the character "d" at the end when called as a string, and commands that take doubles as arguments (like /tp) don't work if the "d" is there. So my suggestion is that, for example, the following command should be considered valid:

/tp @s ~ ~5.5d ~

which it currently isn't.

This will make for much less hassle when using macros with any numeric value that isn't an integer (a short, byte, double, or float).