Update 02.5.md
Update 02.5.md

section 02.5 (object-oriented) added

astaxie/build-web-application-with-golang,admpub/build-web-application-with-golang,admpub/build-web-application-with-golang,astaxie/build-web-application-with-golang,admpub/build-web-application-with-golang,admpub/build-web-application-with-golang,astaxie/build-web-application-with-golang