For Block implementation of disqus comments, we check if the disqus field is enabled on nodes and users.
Removed redundant config variable 'blocks'.when disqus is enabled on blocks with the field configured, disqus comments are rendered as blocks instead of fieldformatter.
Updated the admin form and help page text with removal of config variable 'blocks'.
Removed buildForNodeEntity() and buildForUserEntity() method and generalized the disqus comments blocks to all entities.
Injected the AccountInterface object to DisqusBaseBlock.
Updated cache configuration for DisqusBaseBlock and DisqusCommentsBlock by implementing the defaultConfiguration() method.
Updated PHPdoc.
Injected DisqusManager and Request object to DisqusBaseBlock
Fixed the cache max_age for DisqusBaseBlock to 3600secs with no contexts(earlier as DRUPAL_CACHE_GLOBAL).
Still do need to fix the DisqusCommentsBlock cache state to DRUPAL_CACHE_CUSTOM (See #2222293).
Fixed outdated comment.
Merge pull request #12 from angrycodr/Review-and-fix-block-implementations

Fixed block implementation of Disqus comments.