Erubi is a ERB template engine for Ruby. It is a simplified fork of Erubis,
using the same basic algorithm, with the following differences:
- Handles postfix conditionals when using escaping (e.g. <%= foo if bar %>)
- Supports frozen_string_literal: true in templates via :freeze option
- Works with Ruby's -enable-frozen-string-literal option
- Automatically freezes strings for template text when Ruby optimizes it (on
  Ruby 2.1+)
- Escapes ' (apostrophe) when escaping for better XSS protection
- Has 6x faster escaping on Ruby 2.3+ by using cgi/escape
- Has 86% smaller memory footprint
- Does no monkey patching (Erubis adds a method to Kernel)
- Uses an immutable design (all options passed to the constructor, which returns
  a frozen object)
- Has simpler internals (1 file, <150 lines of code)
- Has an open development model (Erubis doesn't have a public source control
  repository or bug tracker)
- Is not dead (Erubis hasn't been updated since 2011)
