priority was not getting picked up when uncompleting a prioritized todo item

fixes issue #7
forgot to update the todo indices after sorting - fixes issue #5
Last fix introduced a regression, unsorted order was lost upon sorting. This should correctly fix issue #5
version bump 1.1.7
can now save current todo.txt file with the 'w' key, resolves issue #6
clear search results if no matches are found, should fix issue #8
version bump to 1.1.8
Merge pull request #1 from AnthonyDiGirolamo/master

update to new version