Makes a copy of the file source to dest. Returns TRUE on success or FALSE on failure.
If you wish to move a file, use the rename() function.
Note: As of PHP 4.3.0, both source and dest may be URLs if the "fopen wrappers" have been enabled. See fopen() for more details. If dest is a URL, the copy operation may fail if the wrapper does not support overwriting of existing files.
If the destination file already exists, it will be overwritten.
Note: Windows compatibility: If you copy a file with no size, copy() will return FALSE, but the file will be correctly copied.