Change order of path to activator in PATH variable

I had problems with setting the path to activator and/or play when the path came after the content of the PATH variable when using ubuntu. I think it is less error-prone when we add the activator path at the beginning of the PATH variable.
Upgrade to sbt-native-packager 0.7.2.
Merge pull request #2922 from nastra/master

Change order of path to activator in PATH variable
Forward port docs from 2.2.x branch regarding new preferred way to use with intellij
Merge pull request #3192 from benmccann/intellijdocs

Forward port docs from 2.2.x branch regarding new preferred way to use intellij
Merge pull request #3191 from benmccann/native-packager-0.7.2

Upgrade to SBT native packager 0.7.2
Aliased column parser: specs & doc.