add a return value
creat and open file methods have been finished.
first 4 methods have been done.
5 finished
assignment 1 has been finished by yangyangxie
lastest version of assgin1
add some necessary comments to the code
spell check;
change the format.
final version of assign 1
add more error indicators
Add makefile
Makefile
fianl version
Update README.md
Readme
Modify readme and makefile
assignment1
jerry
Merge branch 'jerry' of github.com:axieyangb/DatabaseOrganization into jerry

Conflicts:
	assign1/cs525_project.xcodeproj/xcuserdata/yuzhang.xcuserdatad/xcschemes/cs525_project.xcscheme
	assign1/cs525_project.xcodeproj/xcuserdata/yuzhang.xcuserdatad/xcschemes/xcschememanagement.plist
	assign1/cs525_project/dberror.h
	assign1/extraCredits/calcAvgScore/calcAvgScore.xcodeproj/xcuserdata/xieyangyang.xcuserdatad/xcschemes/calcAvgScore.xcscheme
	assign1/extraCredits/calcAvgScore/calcAvgScore.xcodeproj/xcuserdata/xieyangyang.xcuserdatad/xcschemes/xcschememanagement.plist
	assign2/assign2.xcodeproj/project.xcworkspace/contents.xcworkspacedata
	assign2/assign2.xcodeproj/project.xcworkspace/xcuserdata/xieyangyang.xcuserdatad/UserInterfaceState.xcuserstate
	assign2/assign2.xcodeproj/xcuserdata/xieyangyang.xcuserdatad/xcschemes/assign2.xcscheme~HEAD
	assign2/assign2.xcodeproj/xcuserdata/xieyangyang.xcuserdatad/xcschemes/xcschememanagement.plist~HEAD
	assign2/assign2/assign2/assign2.xcodeproj/project.pbxproj
	assign2/assign2/assign2/assign2.xcodeproj/project.xcworkspace/contents.xcworkspacedata
	assign2/assign2/assign2/assign2/dberror.c
	assign2/assign2/assign2/assign2/dberror.h
	assign2/assign2/assign2/assign2/storage_mgr.h
	assign2/assign2/assign2/assign2/test_helper.h