more explicit description of symbol styles
Added Windows-specific buildsteps module.
Right now it only contains a `Robocopy` step.
Ability to specify a timezone for a P4 server

The Perforce server used with `P4Source` may be in a different time zone
than the Buildbot master, which would cause, for example, changes to be
displayed in the wrong place on the Waterfall display.

This change lets you specify a timezone for the server. Changelist times
will be converted from that timezone to the local timezone before being
added to the Buildbot master.
Fixed Robocopy step status

Robocopy actually returns a combination of flags to indicate
success/warning/failure status.
Added information about Robocopy exit codes.
Added documentation about Robocopy step.
P4: Use config.error, instead of collecting errors by hand.
P4: Use tools provided by CompositeStepMixin.
Reason: allow 'reason' to be overriden in Schedulers and show in Builder page
Reason: update docs and release notes
Removed docstring for Robocopy step.

All usage information is only in the documentation page now.
Documentation about timezone support in P4 changesource
Release notes for Robocopy and P4 changes.
Fixed P4 source unit tests on Windows

This is because P4 normalizes slashes/backslashes, so we need to set our
expectations right.
Added unit tests for Robocopy step.

Fixed whitespace.
Don't pass `/UNICODE` to Robocopy by default.
Added more information about Robocopy in the docs.
Docs: update some index references
repo codingStyle fixes

- repo step and unit tests are now pep8 compliant
- fixed camelCase for repo step parameters
- removed usage of properties as input of the step.
  Its now job of use to choose which property name he wants via renderable
- added test on repo download from changesource
- update doc and release notes

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
repo: add RepoDownloadsFromChangeSource renderable

Suggestion from Tom to put this away from the step code.
In cunjunction with FlattenList, this works well.

+ some more minor review handling

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>