Add support for unverified SSL connections

Sometimes it is required to download a file using SSL from a server
using a self-signed or otherwise unverifiable SSL certificate. This
commit introduces a new parameter, :verify_peer, which accepts a boolean
true/false argument which when set to true allows download from an
unverified peer.
Rename name parameter to path

It is not necessary for a type to have an explicitly defined name
parameter. In order to align with other file-based types, it is more
intuitive to use a parameter named "path" to specify where in the local
filesystem a new file should be created, and this should be the namevar
of the type.

This commit changes the namevar to path. It is backwards-compatible with
usage of the "name" parameter due to how namevar works.
Merge pull request #5 from reidmv/name_to_path

Rename name parameter to path
Merge pull request #3 from reidmv/verify_peer

Add support for unverified SSL connections
Added checksum check after fetch

Also check a file checkum after we have fetched the file. That is if the checksum is specified
Merge pull request #6 from hajee/master

Added checksum check after fetch