workaround issue 9634
Move checkCTFEable to std.exception.assertCTFEable, and use it
fix Issue 10220 - `array` doesn't work with disabled default construction
Issue 10265 - RandomSample fails when passed an InputRange as input

 * Issue fixed by making presence of save() property conditional
   on input being a ForwardRange.
Unittests for randomSample being passed an InputRange.

The assignment of _input = input has been moved from
initialize() to the constructors so as to avoid
problems with nested structs.
Merge pull request #1329 from 9rnsr/fix10220

[REG2.064a] Issue 10220 - `array` doesn't work with disabled default construction
Improve Issue 10220 fix.

Improves pull #1329.

Issue URL: http://d.puremagic.com/issues/show_bug.cgi?id=10220
Merge pull request #1334 from denis-sh/improve-Issue-10220-fix

Improve Issue 10220 fix.
Merge pull request #1290 from blackwhale/regex-9634

Workaround issue 9634
Merge pull request #1332 from WebDrake/randomsample-save

Issue 10265 - RandomSample fails when passed an InputRange as input
fix Issue 10268 - std.typecons.Nullable!JSONValue - error instantiating
Merge pull request #1340 from 9rnsr/fix10268

[REG2.063] Issue 10268 - std.typecons.Nullable!JSONValue - error instantiating
Fix Issue 10317 - Remove text(range) check and avoid recursive instantiation bug.
Merge pull request #1343 from AndrejMitrovic/Fix10317

Issue 10317 - Remove text(range) check and avoid recursive instantiation bug.
Merge branch 'master' of https://github.com/D-Programming-Language/phobos into path-struct