Minor fixes

[stheophil]

A few things I stumbled over.

The fixed header order makes it easier to include your headers if compiling with TC_PRIVATE

The Array ctor fixes the issue that

inline constexpr char sz[] = "Test";

tc::js::Arraytc::jst::js_string(tc::jst::create_js_object, tc::single(sz))

would not compile. Your ctor uses tc::range_value_t which asserts that the range value does not decay.

[stheophil]

My initial solution for the Array ctor was not such a good idea. Using tc::explicit_cast is correct and Arno-approved. Instead of tc::range_value_t I use tc::range_reference_t now and that works.

[stheophil]

Inside namespace tc::js all namespaces must be global qualified namespaces.

If the user declares in typescript

declare namespace std {
    function Test() : void;
}

Then just writing std::forward inside namespace tc::js will fail because in the generated header

namespace tc::js {
    using std = js_defs::_js_jstd;
}

with error message

js_bootstrap.h:138:46: error: no template named 'forward' in 'tc::jst::no_adl::js_reftc::js_defs::_impl_js_jstd'; did you mean 'boost::forward'?

[yeputons]

Thanks! I've added same code for ReadonlyArray and added a test; created a separate issue for tracking the global qualification (#2)