Prevent slicing beyond bounds.

Apply same fix as in #325.

Fixes #333 ArraySliceError.

Remove deprecated -check-printf-calls dflag for LDC

It's deprecated since LDC v1.31, as `pragma(printf)` (used by
core.stdc.stdio) is much better and supported by all compilers.
Additionally, I haven't found a single printf occurrence in this
repo here.

Merge pull request #326 from veelo/ci-dip1000

Test DIP 1000

Regenerate the parser.

Merge pull request #299 from John-Colvin/patch-3

silence an escaping reference deprecation

Merge pull request #289 from veelo/wiki_update

Update wiki sub repository version.

Merge pull request #269 from skoppe/better-error

keep track of the longest failed match to improve error messages

Merge pull request #251 from veelo/dup

Dupping and comparing mutable/immutable parse trees.

Merge pull request #251 from veelo/dup

Dupping and comparing mutable/immutable parse trees.

Merge pull request #243 from wilzbach/run-dlang-io

Add a button 'run.dlang.io' button