change kvstore_env.sh, remove JAVA_HOME setting.
change kvstore_env.sh
add compress function
Almost finish structure, compressed part not finished.
Merge branch 'master' of github.com:jokes000/kvstore
simple modify
Merge branch 'master' into identify

Conflicts:
	.gitignore
	src/main/java/cn/edu/sjtu/se/kvstore/common/Data.java
	src/main/java/cn/edu/sjtu/se/kvstore/db/KVstore.java
	src/main/java/cn/edu/sjtu/se/kvstore/utils/InputHandler.java
	src/main/scripts/kvstore_env.sh
test