Add -p/--profile flag to enable cpu/memory profiling

1. Compile the binary with the profiling flag in it.
2. Run the binary with profiling enabled: ./wtf -p
3. Run the go profiling tool against the resulting *.pprof file:

    go tool pprof --pdf /path/to/wtfbinary /var/path/to/cpu.pprof >
profile.pdf

4. View pretty PDF file

flags/flags.go

@@ -13,6 +13,7 @@ import (
 type Flags struct {
 	Config  string `short:"c" long:"config" optional:"yes" description:"Path to config file"`
 	Module  string `short:"m" long:"module" optional:"yes" description:"Display info about a specific module, i.e.: 'wtf -m=todo'"`
+	Profile bool   `short:"p" long:"profile" optional:"yes" description:"Profile application memory usage"`
 	Version bool   `short:"v" long:"version" description:"Show version info"`
 }