ClosedXML 0.87.1

#148 Improve conditional formatting loading and saving #149 Update test for correctly testing time value as string #154 Shift page breaks #157 Fix maths / statistical functions #158 Explicitly ignore custom sheet view elements. #159 Force OpenXMLValidator to run under invariant culture #172 Allow pivot table field to be a value field and a row/column/filter #173 Cap column width at 255 #179 Pivot table loading enhancements and collapsing fields #180 Implement sheet zooming #185 Correctly deduce data type from number format string if data type i #186 Deduce default header and footer font from worksheet #199 Classic layout should be disabled by default. #200 Preserve whitespace in cells. #203 Remove orphaned drawings from worksheets #204 Better detection of numerical data types. Not only System.Double. #212 Preserve cell format when inserting table or data #214 Don't reference cell to get row height #222 Add VmlDrawing Id's to context to avoid reuse. #231 Text() function - return string as is if input value is already a s #232 Column.AdjustToContents(): Inspect worksheet and table autofilters #233 Don't crash when file contains multiple default styles