update to newer jetty
parser is expects now standard property style
Fix #77 : support json object into header
fixes #132 by moving all config keys into a constant interface.
It's not yet optimal (as there is not yet any separation between the various rendering engines), but at least it's a good start, no ?
Merge branch 'master' of https://github.com/jbake-org/jbake into masterV

Conflicts:
	pom.xml
	src/main/java/org/jbake/app/Parser.java
	src/main/java/org/jbake/launcher/JettyServer.java
	src/main/resources/default.properties
Merge branch 'master' of https://github.com/jbake-org/jbake
update jacoco to latest version, 0.6.X does not work with jdk 8
Fix for Initializing jbake project in selected directory #147

 * -t parameter for specify template to use
Tests for init parameters parsing, assertj update
Merge pull request #151 from mariuszs/topic/init-params

Fix for Initializing jbake project in selected directory #147
Fixes #155
Small simplification for Initializing jbake project in selected directory #147 #151

* default template should be defined only once
Merged in #114.
Merged in #158.
Merge pull request #142 from Vad1mo/master

update jacoco to 0.7.X as 0.6.x does not support jdk 8
Merge pull request #156 from mariuszs/topic/init-params-cleanup

Default template should be defined only once
Cleaned up config keys and added meanings for rest of them.
Merged in #134.
Fixes #153.
Fixes #150.
Added default value when rendering index/archive/sitemap/tags/feed.