Page Breaks - round one

This sets up the basic col and row break creation and serialization.
You can specify either a string reference like "C7" or provide an
Axlsx::Cell instance to specify the break point.

Serialization is working cleanly but excel does not automatically
render those breaks yet. You need to switch to page preview mode.

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/axlsx/workbook/worksheet/row_breaks.rb b/lib/axlsx/workbook/worksheet/row_breaks.rb
index 8a826ed1..2af7216d 100644
--- a/lib/axlsx/workbook/worksheet/row_breaks.rb
+++ b/lib/axlsx/workbook/worksheet/row_breaks.rb
@@ -14,10 +14,14 @@ module Axlsx
       @list << Break.new(options)
       last
     end
-
+    # <rowBreaks count="3" manualBreakCount="3">
+    # <brk id="1" max="16383" man="1"/>
+    # <brk id="7" max="16383" man="1"/>
+    # <brk id="13" max="16383" man="1"/>
+    # </rowBreaks>
     def to_xml_string(str='')
       return if empty?
-      str << '<rowBreaks count="' << @list.size << '" manualBreakCount="' << @list.size << '">'
+      str << '<rowBreaks count="' << @list.size.to_s << '" manualBreakCount="' << @list.size.to_s << '">'
       each { |brk| brk.to_xml_string(str) }
       str << '</rowBreaks>'
     end