Currently when configured without-ssl the build will fail when trying
to run the tools/doc/node_modules, and .docbuildstamp make targets:

internal/util.js:97
    throw new ERR_NO_CRYPTO();
    ^
Error [ERR_NO_CRYPTO]: Node.js is not compiled with OpenSSL crypto
                       support
    at assertCrypto (internal/util.js:97:11)
    at crypto.js:31:1
    ...
    at Object.<anonymous>
       (/node/deps/npm/node_modules/uuid/lib/rng.js:4:14)
    at Module._compile (internal/modules/cjs/loader.js:689:30)
    ...
make[1]: *** [tools/doc/node_modules] Error 1

This commit adds crypto check to these targets to allow the build to
pass.

Currently when configured without-ssl test-heapdump-http2.js will fail
with a missing crypto message.
This commit moves the require of http2 to after the crypto check.

Currently when configured without-ssl test-request-arguments.js will
fail with a missing crypto message.
This commit moves the require of https to after the crypto check.

This commit moves the declaration of node_use_openssl so that it comes
before the first usage as it needs to be available to the ifeq
conditions.