TACHYON-120 Fail to cast String to other object.

Currently JsonObject.get just directly cast parameter Object to the
generic T type. This could generate class cast exception such as
the one from String to DependencyType.

Modify the code to use Jackson JSON formatter instead.
Conver the ObjectMapper in JsonObject to static final per discussion
at http://stackoverflow.com/questions/3907929/should-i-make-jacksons-objectmapper-as-static-final
Remove unneded supressWarning annotation.
Revert "Remove unneded supressWarning annotation."

This reverts commit 50261219cec6021b75b294e5152c4f9530f31d11.
Update the patch to use TypeReference to maintain collection type.
Add unit test for EditLogOperation. For now adding just for CREATE_DEPENDENCY.
Add the assert tests to verify content parsed.
Update import statements ordering.
add method to get FQDN hostname from NetAddress and InetSocketAddress
change system.out.println to LOG.debug because println will affect TfsShellTest
change hostname to FQDN hostname in package master
change hostname to FQDN hostname in package worker
change method to get local hostname and local ip address to methods in NetworkUtils
add unit test to NetworkUtils
format
format
when not local, the get worker call loops forever
avoid unnecessary toString and concatenation
TACHYON-15 Tachyon shell hang when trying to get multi blocks file.
Add unit test to check for FileInStream EOF.