Update nginx from 1.17.4 to 1.17.5.
Update njs module from 0.3.5 to 0.3.6.
Sync third-party fastdfs module version with www/nginx.

<ChangeLog for nginx 1.17.5>

*) Feature: now nginx uses ioctl(FIONREAD), if available, to avoid

reading from a fast connection for a long time.

*) Bugfix: incomplete escaped characters at the end of the request URI

were ignored.

*) Bugfix: "/." and "/.." at the end of the request URI were not

normalized.

*) Bugfix: in the "merge_slashes" directive.

*) Bugfix: in the "ignore_invalid_headers" directive.

Thanks to Alan Kemp.

*) Bugfix: nginx could not be built with MinGW-w64 gcc 8.1 or newer.

</ChangeLog>

<ChangeLog for njs 0.3.6>

nginx modules:

*) Improvement: getting special headers from r.headersIn.

Core:

*) Feature: added new Function() support.

*) Feature: added Number.prototype.toFixed().

*) Feature: added Number.prototype.toPrecision().

*) Feature: added Number.prototype.toExponential().

*) Improvement: making "prototype" property of function

instances writable.

*) Improvement: limiting recursion depth while compiling.

*) Improvement: moving global functions to the global object.

*) Bugfix: fixed prototype mutation for object literals.

*) Bugfix: fixed heap-buffer-overflow while parsing regexp literals.

*) Bugfix: fixed integer-overflow while parsing exponent

of number literals.

*) Bugfix: fixed parseFloat().

*) Bugfix: fixed Array.prototype functions according to the specification.

The following functions were fixed: every, includes, indexOf, filter,
find, findIndex, forEach, lastIndexOf, map, pop, push, reduce,
reduceRight, shift, some, unshift.

*) Bugfix: fixed handing of accessor descriptors in Object.freeze().

*) Bugfix: fixed String.prototype.replace() when first argument

is not a string.

*) Bugfix: fixed stack-use-after-scope in Array.prototype.map().

*) Bugfix: Date.prototype.toUTCString() format was aligned to ES9.

*) Bugfix: fixed buffer overflow in Number.prototype.toString(radix).

*) Bugfix: fixed Regexp.prototype.test() for regexps with backreferences.

*) Bugfix: fixed Array.prototype.map() for objects with nonexistent values.

*) Bugfix: fixed Array.prototype.pop() and shift() for sparse objects.

*) Bugfix: fixed Date.UTC() according to the specification.

*) Bugfix: fixed Date() constructor according to the specification.

*) Bugfix: fixed type of Date.prototype.

Thanks to Artem S. Povalyukhin.

*) Bugfix: fixed Date.prototype.setTime().

Thanks to Artem S. Povalyukhin.

*) Bugfix: fixed default number of arguments expected by built-in functions.

*) Bugfix: fixed "caller" and "arguments" properties of a function instance.

Thanks to Artem S. Povalyukhin.

</ChangeLog>