fix Issue 12810 - PrimaryExpression grammar does not allow type constructors

List grammars for `immutable(int).init` and `immutable(int)(1)`.
fix Issue 13310 - Old style multiple alias declaration not documented
fix Issue 13329 - AutoDeclarationX grammar lists '=' token and template parameters in the wrong order
Merge pull request #634 from 9rnsr/fix_grammar

Fix grammar issues 12810, 13310, 13329