Whitespace and formatting fix

No code or functionality change
Remove redundant list of targets

After #118, we have a separate target (help) to list all available
targets. Having this list in a single place is better, since we don't
have to make changes in multiple places when things change.
Make all executables overridable

This is helpful for #119 which will add support for colorgcc
Change the next version to 1.0.0, instead of 0.13.0

Lot of changes went it for this release and the code is stable enough
for 1.0.0