[Refactoring] Tweak code style in interpreter
[Refactoring] A small code flow improvement in AndAndExp and OrOrExp
[Refactoring] Clean up statement interpretation
Add -verrors=num switch to control error limit
Add -verrors=0 for fail_compilation tests by default
Remove -verrors swithc from the help messages

Save the lines of help message so it's not very useful for the compiler users.
Merge pull request #4189 from 9rnsr/refactor_ctfe

[Refactoring] improve CTFE interpreter code
Merge pull request #4184 from 9rnsr/sw_verrors

Add a new compiler switch -verrors=num to control error report limit