.PHONY should be placed after `all'

Because some make (e.g. nmake) recognize it as a normal rule definition and if it's the first rule, make runs it as a default rule.
Consequently `all', `test' and `clean' are all ran (because they are depended by .PHONY), and builded files are cleaned.
Merge pull request #1824 from unak/patch-1

.PHONY should be placed after `all'