Added multicolumn test file
Included new test file in setup_package.py
Mark bs4 dependency for pytest in html test
Removed leading/trailing whitespace from data in HTML output, switched to izip
Changed correct_table to identify_table and fixed docstring
Made lack of bs4 raise an ImportError instead, fixed html test
Added check for ImportError in _guess
Fixed test for no bs4
Changed ImportError to OptionalTableImportError and fixed test accordingly
Accounted for possible tag nesting or lack of header in HTML files, fixed tests accordingly
Added option of not using multicols for output
Included comment about HTML reader/writer in CHANGES.rst
Added BeautifulSoup to optional dependencies list in docs
Changed docs to reflect that bs4 is only necessary for parsing
Removed check for nesting inside table
Changed identify_table to check tag rather than parent
Added test for rereading HTML output of VOtable
Restructured reader by making HTMLInputter responsible for finding table data
Removed VOtable test
Moved check for <tr> tags to HTMLInputter, removed old test