Added cms_concepts
Update README.md

Update readme file
Update CMS_concepts.md

Added table of contents
Renamed files and added tutorial document
Update concepts.md

Updated
Update concepts.md

Updated default regions
Merge pull request #15 from jvelilla/roc_template

Roc template
Removed default_theme.
Update theme and smarty theme description
Fixed non void-safe compilations, and cleaned .ecf files.
+Cosmetic
Update concepts.md

Added references to the important classes.
Removed shared_error from CMS_API
Added Missing theme and Missing tempalte classes.
Updated CMS_RESPONSE to handle missing template and send a 503 status code
with a raw response.
Added comments.
Update concepts.md

Updated concepts with Modules and Hooks
Update concepts.md

Updated Concepts table of contents
Merge branch 'roc_template' of https://github.com/jvelilla/ROC into roc_template
Added {CMS_SETUP}.modules_enabled: CMS_MODULE_COLLECTION
Updated {CMS_SERVIDE}.intialize_modules to use the new feature {CMS_SETUP}.modules_enabled
Updated cms_hook_block description
Refactor raname {CMS_SETUP}.modules as {CMS_SETUP}.available_modules
Refactor raname {CMS_SETUP}.modules_enabled as {CMS_SETUP}.enabled_modules
Updated code to use the new features names.
Update concepts.md

Updated concepts