TST: HTMLFormatter does not die on unicode frame GH6098
BUG: HTMLFormatter does not die on unicode frame GH6098
Merge pull request #6112 from y-p/PR_GH6098

BUG: HTMLFormatter does not die on unicode frame GH6098
TST: get_options_data ValueError if given only one of month/year GH6105
BUG: get_options_data should raise ValueError if given only one of month/year GH6105
Merge pull request #6114 from y-p/PR_GH6105

BUG: get_options_data should validate it's arguments GH6105
TST: add _skip_if_no_xlrd() to test GH5583
Merge pull request #6115 from y-p/PR_GH5583_fix_skip

TST: add _skip_if_no_xlrd() to test GH5583
ENH: allow legend='reverse' in df.plot() GH6014