Update scripts for creating 3.3.x documentation

[marc1706]

Todo:

• Update bamboo config
• Update scripts for developer documentation
• Update scripts for user documentation
• Test correct creation of scripts
• Update website related scripts (should reference the correct branch for 3.3.x etc.)
• Update Area51 to contain 3.3.x coding guidelines instead of master ones for 3.3.x (!!)
• Make sure link to styles demo for 3.3.x works (@michaelcullum ?)
• Check links to 3.3.x pages on area51
• Add +x to build_code_changes_33.sh
• Use different stylesheet for 3.3.x (?)