- split the ClassReader accept() method into several methods (readField,...

- split the ClassReader accept() method into several methods (readField, readMethod, readCode, readFrame, etc), each using local variables with the smallest possible scope. Required the addition of a Context helper class. Makes the code more readable, a little bit bigger (+4%), but also faster (1.12 speedup for the deserialize performance test).
- switched to the Java code style conventions, applied Eclipse auto format on all files.