Log Message:
Update to 2006.1, based on PR pkg/35287 by Marc Tooley. From the changelog:

* Client file tamper checking
* New client option 'SubmitOptions'
* Speedup of 'p4 submit' branched files
* 'Automatic' labels
* Improved management of remote depots
* New MaxLockTime in 'p4 group'
* Improved license file handling
* User file access tracking
* 'p4 integrate' improvements
* Optimization of head revision operations
* Speedup for the 'integ' command
* Early release of db.working/db.resolve during sync
* Server Performance Tracking
* Spec depot interferes less with other commands
* Special handling for @changelist
* Speedup for clients with many opened files
* External authentication triggers
* UTF-16 support
* Speedup for the 'dirs' command
* Speedup for the 'obliterate' command
* Btree passive reorganization
* MapState simplification
* Spec depot
* Partial filetypes
* Delete triggers
* Authorization and security levels
* New login/logout commands
* New trigger support
* New indirect integration default
* New smart resolve logic
* Filepaths that contain characters @#%* can be added to the depot
* New tag command provides easy way to assign a label to a filelist
* Optimization for frequent syncs
* Label use speedups
* Locking and memory use improvements
* Speedups for large client views and protections tables
* Indirect integration much faster
* New monitor command displays status of running p4 processes
* Integrate across distant branches
* New annotate command shows history of lines in a file
* Sharing clients using multiple client roots
* Sprucing up diffs
* tempobj filetype redux
* New protection level for semi-super users

and a bunch of other features and bug fixes.