vendor: update all dependencies

* Update all dependencies
  * Remove all `[[constraint]]` from Gopkg.toml
  * Add in the minimum number of `[[override]]` to build
  * Remove go get of github.com/inconshreveable/mousetrap as it is vendored
  * Update docs with new policy on constraints

vendor/github.com/sevlyar/go-daemon/lock_file.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"os"
-	"syscall"
 )
 
 var (
@@ -106,19 +105,5 @@ func (file *LockFile) Remove() error {
 		return err
 	}
 
-	// TODO(yar): keep filename?
-	name, err := GetFdName(file.Fd())
-	if err != nil {
-		return err
-	}
-
-	err = syscall.Unlink(name)
-	return err
-}
-
-// GetFdName returns file name for given descriptor.
-//
-// BUG(yar): GetFdName returns an error for some *nix platforms when full name length of the file is greater than 0x1000.
-func GetFdName(fd uintptr) (name string, err error) {
-	return getFdName(fd)
+	return os.Remove(file.Name())
 }