Some UI fixes for Extend Bolt page.
Merge pull request #1757 from xiaohutai/bolt-extends-ui-fixes

Some UI fixes for Extend Bolt page.
Replacing 'cutesy' images with different ones, for Bolt 2.0
Merge branch 'master' of github.com:bolt/bolt
Edited dokumentation
Removed some excluded directories
Added sniff requiring spaces around string concatenating operator
Commented unused sniff
Added sniff requiring no brackets for echo
No Abstract prefix for "BaseExtension" needed anymore
Revised concatenation sniff
copy/paste case
ignore multiple class in same file
function styling
Coding style: concatenation operator
only catch errors if they are in an extension
Merge pull request #1759 from rarila/codesniffer

Codesniffer enhanced
Merge pull request #1760 from rixbeck/cleanup-cs-fixes

Cleanup CodeSniffer fixes in #1755
Merge pull request #1761 from rossriley/extensions-improvements-fixes

only catch errors if they are in an extension
Merge pull request #1762 from rarila/code-styling

Coding style: concatenation operator