Merge topic 'compile-features-for-language-standards'

9a8d758c Help: Document language standard meta-features
df252db1 Features: Test cycle diagnostic with language standard meta-feature
6d5fb0e0 Features: Test feature propagation with language standard meta-feature
a34b98a8 WCDH: Ignore language standard meta-features
b0996a3f Features: Add meta-features requesting awareness of a particular standard
8b6cc251 Features: Centralize per-compiler recording macros
2d23f7b2 Features: Do not record features on MSVC < 2010