Add examples directory

[mondeja]

Examples

• Simple README file translation (CLI)
• Simple README file translation (programmatic API)
• Bash script translating a set of languages
• Programmatic API translating a set of languages
• mdpo2html with Python-Markdown (CLI)
• mdpo2html with Python-Markdown (programmatic API)
• Custom parsing using event hooks (programmatic API)
• Custom parsing using event hooks (CLI):
  • Disable a block by content (see Feature request: md2po argument to exclude lines based on character matching #227)