fix logic in agent.lua regarding to config.

so that only one of the three options can be used. This commit fixes the
failed "clearer logic" in #526.
Example for monitoring plugin configuration
by using process_mon
updated the metrics to match the plugin
move old into.lua code to lib/agent.lua
wip: add Connection class
bump base; disable /tests/agent-protocol
bump base; added relavent files
bump base with new fixes
bump for the base merge to master
Merge pull request #573 from virgo-agent-toolkit/songgao/refactor

Refactor Work in Progress
fix(proxy): fixes for proxy
Merge pull request #585 from virgo-agent-toolkit/songgao/proxy

Proxy
Remove dead code
Merge pull request #587 from virgo-agent-toolkit/fix/cleanup_dead_code

Remove dead code
change clone URLs
Merge branch 'master' of github.com:racker/virgo
Add signals to readme
fix formatting
base base
Merge pull request #592 from virgo-agent-toolkit/fixes/change_pid_permissions

base base