Add <system> section to set core parameters in configuration file
Remove unused Config methods
fix out_file formatter
Fix typo of CONTRIBUTING
use config_param
Merge pull request #367 from sonots/fix_out_file_formatter

fix timezone issue of out_file formatter
Remove obsoleted TcpInput

StreamInput based TcpInput is obsoleted since 2+ years ago.
So we can remove this class for newer plugin
Add udp input plugin
Add tcp input plugin
in_syslog uses socket utility handlers instead of own handlers
fix to use rake argument to run specified test only
remove used env value from ENV, not to affect to any other code
revert 38fbd7a20f1ac40ef74675c4440c6bf40541de61 and bf573f272821cfcea0cc476028ec5b7172ddd141, then add comment for test execution
add time_default_current (default true) to disable filling current time when time is not produced by parser result
Add config_param "time_default_current" not to set current time into parse result
 * By setting current time, caller cannot know "time" is from whether parse result or current time
   * it brings troubles especially in case for filter plugins like fluent-plugin-parser
 * naming problem:
   * 'time_' prefix seems important for me
Support use_v1 argument to enable V1 configuration in test module. fixes #371
Merge pull request #365 from fluent/support-system-parameters-in-config-file

Add <system> section to set core parameters in configuration file
Remove trailing delimiter on both udp and tcp
Fix feature from config_param to attr_accessor
 * not to be enabled on plugin direct use
Add other format tests to udp and tcp inputs