minor fix,if path does not include :
fix #265
Merge pull request #271 from shavac/master

minor fix,if path does not include ':', beego will crash of "index out of range"
fix #235
orm fix for support custom field
orm fix sqlite3 time convert
Merge branch 'master' of github.com:astaxie/beego
fix #270

同时支持全部小写和驼峰写法
fix #236