Version bump to 2.3.0
Version bump to 2.3.0

mezza/rubyXL,ThijsWouters/rubyXL,mezza/rubyXL,weshatheleopard/rubyXL,99cm/rubyXL,weshatheleopard/rubyXL,parallel588/rubyXL,ThijsWouters/rubyXL,parallel588/rubyXL,weshatheleopard/rubyXL,parallel588/rubyXL,ryanmark/rubyXL,99cm/rubyXL,ryanmark/rubyXL,99cm/rubyXL,mezza/rubyXL,ryanmark/rubyXL