Metacat

added more locking support and support for remote update of files.

added more locking functionality for replication

AccessControlList
- methods for parsing and loading acl file
- checkup method for permission for given principal on given resource
DBQuery
- checkup for READ permission using AccessControlList.hasPermission()
DocumentImpl
- using AccessControlList object to parse and load an acl file into xml_access table...

cleaned up code, added new static methods to MetacatReplication for handling static queries and getting URL content.

updated insert handling and added an action to request the time from a remote server.

created locking action in replication servlet and added semi-support to documentImpl to handle documents updatedee by replicatio

Modified stylesheets and server code to use a single "read" action instead
of the earlier "getdocument" and "getrelateddocument" actions. In the
process, developed and started to utilize a new suite of URL "protocol
handlers" that are in the package "edu.ucsb.nceas.protocols" and handle...

Added a new URL protocol handler class for the metacat protocol. This
class will replace the current MetacatURL class in a much simpler and
extensible manner. See the documentation for java.net.URLConnection and
java.net.URL for details.

this class allows the parsing of xml data sent by a replication server to assertain document info about a remote document.

added functionality to allow the replication servlet to assertain and insert user and group info into the local database. started implementation of insert replication handler (it is commented out in this commit)