glsl: Be consistent about '\n', '.', and capitalization in errors/warnings.

The majority of calls to _mesa_glsl_error(), _mesa_glsl_warning(), and
_mesa_glsl_parse_state::check_version() use a message that begins with
a lower case letter and ends without a period.  This patch makes all
messages follow that convention.

Also, error/warning messages shouldn't end in '\n', since
_mesa_glsl_msg() automatically adds '\n' at the end of the message.

Reviewed-by: Matt Turner <mattst88@gmail.com>

src/glsl/ir_function_detect_recursion.cpp

@@ -298,7 +298,7 @@ emit_errors_unlinked(const void *key, void *data, void *closure)
 
    memset(&loc, 0, sizeof(loc));
    _mesa_glsl_error(&loc, state,
-		    "function `%s' has static recursion.",
+		    "function `%s' has static recursion",
 		    proto);
    ralloc_free(proto);
 }