WIP

fixes #226, fixes #169, fixes #235

This one is another very complex PR, but it would allow creating playgrounds for Scramble by making rules evaluation optional and relying on static analysis instead will reduce the amount of bugs due to evaluation issues.

To make this possible a bit more features to inference system must be added:

• Static methods call analysis support
• Late static binding analysis support (proper handing of static::, self::, __CLASS__)
  • Figure out general approach
  • class const fetching
  • Consts fetching
  • new calls
  • Method calls (static, non-static)
  • Props fetching
• Consts fetch type inference support
• Static method calls extensions support
• Add array_keys function support
• Inferring type from array value
• Inferring type from object value

And to Scramble docs generation:

• Rule::* methods inference support (via extensions for now)
• Rules classes better support
  • Database rules (exists, unique) and their methods
  • new Enum|In|* rule creation
• New Rules API
• Documenting statically analyzed rules (rules type)
• Runtime objects -> Types conversion (for class-based rules)