pts-to tests: move helper functions to PTGTester

keep tests in one file and generic functions in another
pts-to: move FixedCategories to tests

This class is used only in tests anyway
pts-to tests: add applyRule(s) to PTGTester

Allow PTGTester use apply rules
ptg tests: add offset to testing pointers

don't use offset -1 everywhere
ptg tests: add notTested helper function

Write message that something has not been tested and add
it to failed tests
remove dumpPointsToSets, merge to move applyRUles to PTG
ptg tests: add tests for applyRule's methods.
saviour