Stop altering the input variables.
fix spacing
Call the block if an error happens instead of raising an exception.

Allow for the user of the launchy library to decide if they want to handle
exceptions or swallow them via a block.
update version to 2.3.0
update to latest fixme
Update documentation for upcoming 2.3.0 release

Also convert to Markdown.
Only use the options that are available after globals are removed.
Add URI parsing to debug output
Only check for file existence if we DO NOT have a scheme
Have the commandline program use the new block feature.
Update manifest before release