add support for some predefined compilation flavors: thread, multi, 64int, 64all, ld and debug; rename threads to thread for consistency with how this flavor is usually named while keeping support for the old flag
add support for install-multiple command
document install-multiple command
remove warning from perl_version_to_integer
set flags not in current variation to ''
detect 64bit platforms and hide 64int and 64all flags automatically
fix comment
fix error on mocked http_get sub
perl_version_to_integer was failing for versions of the form 5.xxx
set $self->{installation_name} from mocked do_install_release
Merge pull request #334 from salva/flavors

another take on allowing one to install several perl variations (and now also versions) on one single command