update README.md.

passed all the tests for A7.

basically implement alias-aware InterConstantPropagation for A7.

fix bugs and passed all the unit tests in A8.

basically implement TaintAnalysis for A8.

copy code in Solver.java from A6 to A7.

copy code from A2 and A6 to A7.

passed all the unit tests for A6.

implement Solver for context-sensitive points-to analysis in A6.

passed all the tests for A5.

basically implement context insensitive pointer analysis.

fix bugs in A4 and implement several function for A5.

fix bugs and passed basic tests.

implement InterSolver and InterConstantPropagation.

implement CHABuilder