Added properly functioning case insensitive match without regex

pandas.core.strings.str_contains should now match case insensitivity properly if given regex=False and case=False.  Also added test cases for case insensitive pandas.core.strings.str_contains with and without regex.
Documentation for str_contains bug in changelog
BUG: grouped hist and scatter use old figsize default
additional common.is_*_dtype tests in core.common
BUG: single column bar plot is misaligned
BUG: Better xaxis handling for partial layout
make better use of dtype tests in nanops
Merge pull request #7547 from toddrjen/nanopsclean

Minor cleanups for nanops
Redesigned pandas.io.gbq to remove bq.py as a dependency for everything except unit testing. Minor API changes were also introduced.
BUG: bug in float64index assignment with a non scalar indexer
Squashed commit of the following:

commit 5e9e0fa29d727953583a116638a9d0db81f9ed21
Author: Michael Mueller <michaeldmueller7@gmail.com>
Date:   Thu Jun 26 19:53:35 2014 -0400

    Fixed issue with empty lines

commit 57b54918b251ab77f000b575d77bcce3affcb27a
Author: Michael Mueller <michaeldmueller7@gmail.com>
Date:   Thu Jun 26 16:31:27 2014 -0400

    Added reference to new functionality in docs

commit a2371638691584416439d3c6a4dd2ef1829dcbe3
Author: Michael Mueller <michaeldmueller7@gmail.com>
Date:   Thu Jun 26 16:26:06 2014 -0400

    Implemented functionality to ignore comment lines, wrote a test
Merge pull request #7587 from cpcloud/float64index-assign-7586

BUG: bug in float64index assignment with a non scalar indexer
BUG: Bug in timedelta inference when assigning an incomplete Series (GH7592)
Merge pull request #7593 from jreback/timedelta_nat

BUG: Bug in timedelta inference when assigning an incomplete Series (GH7592)
BUG/TST: fix tests for groupby nth on Series (GH7559)
TST: tests for GH7594, ensure conversion on tz-aware datetimes in the constructors
Merge pull request #7595 from jreback/tz_aware

TST: tests for GH7594, ensure conversion on tz-aware datetimes in the constuctors
COMPAT: comparisons vs numpy nat not working on windows
Merge pull request #7597 from pydata/nat

COMPAT: comparisons vs numpy nat not working on windows
TST: Change nose.SkipTest to raise nose.SkipTest for io.data.Options.