The functions optionaly exported by this module allows you to open URLs in the
user browser.

A set of known commands per OS-name is tested for presence, and the first one
found is executed. With an optional parameter, all known commands are checked.

The "open_browser" uses the system() function to execute the command. If you
want more control, you can get the command with the "open_browser_cmd" or
"open_browser_cmd_all" functions and then use whatever method you want to
execute it.
