spell checker:
- find the "closest" symbol for the minimum levenshtein distance
- do not report private symbols from import
- remove spurious error messages on private symbols found by the spell checker
- allow ambiguous symbols to be reported
Merge pull request #4143 from rainers/issue13736

Fix 13736 - Spellchecker should prefer symbols from inner scopes
fix Issue 13757 - [CTFE] extern(C) alias declaration does not work in CTFE
fix Issue 13756 - [AA] Allow ref const index on foreach AA iteration
Merge pull request #4152 from 9rnsr/fix13756

Issue 13756 - [AA] Allow ref const index on foreach AA iteration
Merge pull request #4153 from 9rnsr/fix13757

Issue 13757 - [CTFE] extern(C) alias declaration does not work in CTFE
Preparation for the issue 13701 - Hijack object.dup(aa) call to emulate it in CTFE
fix Issue 13701 - Associative array values ignore immutability
Merge pull request #4154 from 9rnsr/ctfe_aa_dup

Preparation for the issue 13701 - Hijack object.dup(aa) call to emulate it in CTFE
Merge pull request #4148 from 9rnsr/fix13701

[REG2.061] Issue 13701 - Associative array values ignore immutability
fix Issue 13760 - Cannot deduce function for object.get
Fix typo in mnemonic in Solaris version of Port::yl2xp1_impl

The instruction is fyl2xp1 and not yl2xp1.
Merge pull request #4157 from redstar/solaris

Fix typo in mnemonic in Solaris version of Port::yl2xp1_impl
convert voidInitLiteral()
Merge pull request #4156 from 9rnsr/fix13760

[REG2.067a] Issue 13760 - Cannot deduce function for object.get
Merge pull request #4158 from WalterBright/voidinitliteral

convert voidInitLiteral()