RTF support

Support of unlimited block name length (issue #1)
RTF support

Single-character quotes are used by default due to trash RTF markup
(issue #1)
RTF support

Added support of placeholder token quotes to solve issue with trash RTF
markup in placeholder's token body (issue #1)
RTF support

Placeholder tokens cleanup from trash RTF markup  (issue #1)
RTF support

Support of placeholder token quotes (issue #1)
RTF support

Block name tokens cleanup from garbage RTF markup (issue #1)
RTF support

Remove extra line breaks