Ignore std error on version discovery

git may print warnings out that can confuse the parsing, and std error
could never provide a trustworthy errorn number anyway. (In my case, it
was providing a tag name which provided a valid but undesirable match,
so I was ending up with the wrong version number)

Change-Id: I61bccacfff20fd4afd8ac8d73b69e2deab50d1c7
unit test config.ConfigErrors.__str__() method

Added unit test on config.ConfigErrors.__str__() method
unit test configure file open error in MasterConfig.loadConfig()

Added a unit test that simulates IOError when opening configure file in
config.MasterConfig.loadConfig(). Check that the expected ConfigErrors
exception is rised.
removed unreachable code in config.MasterConfig.loadConfig()

The call to error() with global _errors set to None, will raise
an exception. Thus following 'raise errors' is never reached.
unit test on loading 'codebaseGenerator' master parameter

Added unit tests on code in buildbot.config.MasterConfig.load_global()
that loads 'codebaseGenerator' master configuration parameter. Test
both loading correct parameter and invalid.
unit test error paths in MasterConfig.load_status()

Test that invalid 'status' option in master config file is
handled properly.
unit test error paths in BuilderConfig.__init__()

Test that invalid nextSlave, nextBuild, canStartBuild and
env arguments to BuilderConfig constructor are handled properly.
updated buildbot.config.MasterConfig.check_locks() unit tests

Updated unit tests of buildbot.config.MasterConfig.check_locks()
method to use lock objects wrapped inside LockAccess objects.
Nowadays this is the recommended style of specifying locks in the
documentation.

Add one new unit test to check that using 'bare' lock objects still
works.
Fix "proeprty" typo
Fix PATCHLEVEL -> LEVEL typo
Uses XML output format of svn info to fetch url

Regex was used with svn info output to fetch url value in
SVN._sourcedirIsUpdatable. French and Norvegian svn versions use
respective language names for url value and not 'URL' in regex.
XML Output format of svn info resolves it

Fixes http://trac.buildbot.net/ticket/2375
Fixes svn tests to match url value in XML output format of svn info
Handle multiple codebases in Grid and Transposed Grid views
Merge branch 'et_setup_version' of git://github.com/jgonzalezmendez/buildbot
Merge branch 'typos' of git://github.com/vrutsky/buildbot
Merge branch 'multiple_codebases_grids_view' of git://github.com/vrutsky/buildbot
change tests to correspond
Merge branch 'pull639'
Merge branch '2375fix' of git://github.com/ShriramK/buildbot
pyflakes