Sending last second message as quoted content

Each of its lines are prefixed with `> ` sign. It is then added to the end
of script
Convert new lines to html equivalents

Now E-Mails are send as HTML content type so it content should be in
proper HTML format

\n will convert to <br />
\n\n will convert to new paragraph
Refactored classes/class-supportflow-emails.php
Refactored code
Sanitizing ticket reply before sending in E-Mail
Methods accidentally called as functions
Merge branch 'master' into quote-outgoing

Conflicts:
	classes/class-supportflow-emails.php
Corrected typo
Merge pull request #190 from VarunAgw/quote-outgoing

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