Required including NSS header in places that depended on
util-file.h including it.
All filestore suricata-verify tests now pass without libnss.
Also enabled detect-file{md5,sha1,sha256} without NSS support.
Currently, unit tests use integer values 1 and 0 to denote pass
and fail status of tests respectively. Modify the unit test
detect-filesha1 to use the PASS/FAIL API instead.
Set flags by default:
-Wmissing-prototypes
-Wmissing-declarations
-Wstrict-prototypes
-Wwrite-strings
-Wcast-align
-Wbad-function-cast
-Wformat-security
-Wno-format-nonliteral
-Wmissing-format-attribute
-funsigned-char
Fix minor compiler warnings for these new flags on gcc and clang.