Version bump to 2.3.4
Version bump to 2.3.4

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