Remove dependencies on sun jvm classes. Instead use reflection to infer
HotSpot options and total physical memory size
Update Hadoop dependency to 1.0.3 as 0.20 has Sun specific dependencies. Also
fix SequenceFileRDDFunctions to pick the right type conversion across Hadoop
versions
Remove unused BoundedMemoryCache file and associated test case.
Use a dummy string class in Size Estimator tests to make it resistant to jdk
versions
Make default hadoop version 1.0.3 in pom.xml
Update expected size of strings to match our dummy string class
Merge pull request #354 from shivaram/ibm-jdk-fixes

Fixes to build and test spark on IBM JVM