fixed a typo in generated smptett
Added smptett support for teletext input
Fixed line break in output for teletext input
Fixed a rare bug with some teletext input

In rare cases, the output had the last line written after the footer (i.e. for
smptett the last </div></tt> was after the last <p>).
Added default style to smptett header
Merge remote-tracking branch 'carlos/master'
Fixed a typo in smptett header
Fixed smptett timeExpression format

Now all timeExperssion in smptett file comply to:
http://www.w3.org/TR/2013/REC-ttml1-20130924/#timing-value-timeExpression
Added support for -startat and -endat for teletext input
Fixed potential timestamp overflow with negative delay

When delay was a large enough negative number, some show_timestamp would
overflow and be set to ridiculously large value.
Init 'ret' variables
Merge branch 'pr/n125_MikaYuoadas'
Merge remote-tracking branch 'carlos/master'
updated teletext changes
Merge branch 'master' of https://github.com/anshul1912/ccextractor