Merge pull request #1 from gheggie/master

Spelling fixes
ENHANCEMENT added permission checks
Merge branch 'master' of git://github.com/sheadawson/silverstripe-blocks
ENHANCEMENT use formatted  singular_names for block type and area dropdowns
MINOR nicer formatting of block classname and area name in gridfield lists
BUGFIX prevent updatecmsfields from running twice on BlockSiteTreeExtension, improve use of singular name on BlockSet page type listing
MINOR removed empty page parents cms tab from BlockSet
Merge branch 'master' of git://github.com/sheadawson/silverstripe-blocks
Update README.md
MINOR name to label on block area names
Merge branch 'master' of git://github.com/sheadawson/silverstripe-blocks
BUGFIX add existing wasn't working
allow changing of block class, added cssclasses field to block
BUGFIX: config preserved in BlockManager