allow runtime setting of Recognition-Timeout

Resolved conflicts:
	lib/punchblock/translator/asterisk/component/mrcp_recog_prompt.rb

send recognition timeout setting as UniMRCP option

allowing dynamic setting of Recognition-Timeout in the MRCP messaging
with speech recognition server

Resolved conflicts:
	lib/punchblock/translator/asterisk/component/mrcp_recog_prompt.rb

add test for setting recognition-timeout header

update changelog