update i2c read interface
refine client_api interface
add ext socket support
always enable ERROR print for diag client
add coding style guideline
fix diagd test complile bug
add pci command

Change-Id: I75508e8f447da40a90a24a9c88a2b74f6458560f
Reviewed-on: http://10.208.24.69:8080/52
Reviewed-by: Xudong Huang <xudongh@juniper.net>
add reset command
add FPAG command
add FPGA test script
add button command
update fpga according review
review update
add rtc command
Merge branch 'master' into ng-srx-es3
add rtc driver layer for stargo