Fix wx.lib.agw.labelbook KeyError exceptions and typos in comments

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxPython/Phoenix/trunk@74481 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Partially revert wx.lib.agw.labelbook leaving only comment typo fixes and fix XPM strings to bytes strings in wx.lib.agw.fmresources

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxPython/Phoenix/trunk@74482 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Use BytesIO with bytes data

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxPython/Phoenix/trunk@74483 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775