code cleanup

Since my latest client is insisting on my using phRETS for his project, I figured I'd contribute to the codebase and get it cleaned up a bit.

Three changes:

1) Renamed constructor to __construct(). Is PHP 5.3 compatibility still mandatory now that it's been EOL'd?

2) Removed unnecessary sanity check in GetMetadataInfo() since this method seems to be an alias  for GetMetadataResources(), which already does its own sanity check. Is GetMetadataInfo() a deprecated method left in for backwards compatibility?

3) Removed unnecessary blank links, such as double blank links between methods and at the end of function before the return statement.

It may be that you prefer the double blank lines between method definitions, and therefore reject this pull request, but I figured I'd give it a shot anyway. Do you have coding standards defined somewhere?