xml escape character "&" is corrupting sheetname on write

[agentjill]

in book.get_sheet_by_name_mut("Sheet2").unwrap().get_cell_mut("A1").set_value("TEST1");

if the sheet name contains xml escape characters for example say Alice&Bob then it is not detecting the Worksheet.

On inspection the ''Alice&Bob'' is being processed as Alice&Bob, that would mean that xml escape character & is not properly read as &.

calling sheet by Alice&Bobis saving the workbook as Alice&&Bob

[MathNya]

@agentjill Thank you for your report. We will address this in the next version update.

[agentjill]

This was addressed in #145.