more complete support for sql language

QueryBuilder for building SQL queries quickly

Context params

fixed uninitialized return error if StartAndGC fails

Proposal for adding a ":" for stack trace printout

Mainly useful for Sublime users with goto anything.

Extra field if username is empty

Typo in the printout of some level's prefixes

udpate ini.go

Update file.go

Print error if occurred in WriteMsg

Allow mail with self-signed certificates

For more information, refer to https://groups.google.com/forum/#!topic/golang-nuts/c9zEiH6ixyw

New pull request for "Panic sometimes occurs at time 00h00 on windows, then the app crashes."

Signed-off-by: devYu <devysq@gmail.com>