PLT-4357 adding performance monitoring (#4622)

* WIP

* WIP

* Adding metrics collection

* updating vendor packages

* Adding metrics to config

* Adding admin console page for perf monitoring

* Updating glide

* switching to tylerb/graceful

vendor/github.com/prometheus/procfs/fixtures/26232/comm

@@ -0,0 +1 @@
+ata_sff

vendor/github.com/prometheus/procfs/fixtures/26232/fd/0

@@ -0,0 +1 @@
+../../symlinktargets/abc

vendor/github.com/prometheus/procfs/fixtures/26232/fd/1

@@ -0,0 +1 @@
+../../symlinktargets/def

vendor/github.com/prometheus/procfs/fixtures/26232/fd/2

@@ -0,0 +1 @@
+../../symlinktargets/ghi

vendor/github.com/prometheus/procfs/fixtures/26232/fd/3

@@ -0,0 +1 @@
+../../symlinktargets/uvw

vendor/github.com/prometheus/procfs/fixtures/26232/fd/4

@@ -0,0 +1 @@
+../../symlinktargets/xyz

vendor/github.com/prometheus/procfs/fixtures/26232/limits

@@ -0,0 +1,17 @@
+Limit                     Soft Limit           Hard Limit           Units     
+Max cpu time              unlimited            unlimited            seconds   
+Max file size             unlimited            unlimited            bytes     
+Max data size             unlimited            unlimited            bytes     
+Max stack size            8388608              unlimited            bytes     
+Max core file size        0                    unlimited            bytes     
+Max resident set          unlimited            unlimited            bytes     
+Max processes             29436                29436                processes 
+Max open files            1024                 4096                 files     
+Max locked memory         65536                65536                bytes     
+Max address space         unlimited            unlimited            bytes     
+Max file locks            unlimited            unlimited            locks     
+Max pending signals       29436                29436                signals   
+Max msgqueue size         819200               819200               bytes     
+Max nice priority         0                    0                    
+Max realtime priority     0                    0                    
+Max realtime timeout      unlimited            unlimited            us        

vendor/github.com/prometheus/procfs/fixtures/26232/stat

@@ -0,0 +1 @@
+33 (ata_sff) S 2 0 0 0 -1 69238880 0 0 0 0 0 0 0 0 0 -20 1 0 5 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 1 0 0 0 0 0 0 0 0 0 0 0 0 0