Prepare for 0.7.5 release.

prepare for 0.7.4 release

Create tag 0.7.3

git-svn-id: https://secure.simplistix.co.uk/svn/xlwt/tags/0.7.3@4885 ac150577-6901-3246-a117-cd8547e6756f

tagging 0.7.2

git-svn-id: https://secure.simplistix.co.uk/svn/xlwt/tags/0.7.2@3853 ac150577-6901-3246-a117-cd8547e6756f

tagging 0.7.1

git-svn-id: https://secure.simplistix.co.uk/svn/xlwt/tags/0.7.1@3789 ac150577-6901-3246-a117-cd8547e6756f

tagging 0.7.0

git-svn-id: https://secure.simplistix.co.uk/svn/xlwt/tags/0.7.0@3483 ac150577-6901-3246-a117-cd8547e6756f

take a tag shortly before removing the ExcelFormula stuff

git-svn-id: https://secure.simplistix.co.uk/svn/xlwt/tags/excelformula@3303 ac150577-6901-3246-a117-cd8547e6756f

tag the trunk as it was in pyExcelerator's CVS repo on sourceforge

git-svn-id: https://secure.simplistix.co.uk/svn/xlwt/tags/pyExcelerator@2637 ac150577-6901-3246-a117-cd8547e6756f