TST: util/testing improvements

assertRaises and assertRaisesRegexp are now with-statement-compatible,
refactored assert_panel_equal and removed check_index_freq from
assert_series_equal.
Merge pull request #4450 from jtratner/change-range-zip-in-docs

DOC: lrange, lzip --> list(range and list(zip
Merge pull request #4451 from jtratner/better-assert-tests

TST: pandas/util/testing : test improvements and cleanups
BUG: fix truncation for astype(str)
Merge pull request #4437 from cpcloud/fix-astype-calls

BUG: fix string truncation for astype(str)
DOC: fix tz doc bug
BUG/OFMT: fix spurious tuple repring of bytes types in python 3
CLN: clean up _is_sequence
ENH/CLN: add string and binary types compat object
PERF: enhance HDFStore Table writing performance

CLN: removed is_searchable (no longer needed)
Merge pull request #4456 from cpcloud/fix-py3-bytes-repr

BUG/OFMT: fix repring of python3 bytes objects
BUG: Fix Panel instance variable namespace issue GH3440
Merge pull request #4459 from danbirken/panel-instance-name-fix

BUG: Fix Panel instance variable namespace issue GH3440
BUG: values array for non-unique, interleaved cols incorrect
Merge pull request #4460 from Komnomnomnom/frame-dupe-cols

BUG: values array for non-unique, interleaved cols incorrect
Merge pull request #4457 from jreback/hdf_opt

PERF: enhance HDFStore Table writing performance
BUG: bug when using chunksize and writing ndim > 2
Merge pull request #4462 from jreback/hdf_opt2

BUG: bug when using chunksize and writing ndim > 2
ENH: allow where to be a list/array or a boolean mask of locations (GH4467)
Merge pull request #4470 from jreback/hdf_coord

ENH: allow where to be a list/array or a boolean mask of locations (GH4467)