[lvti] - first prototype pushed

[Maurizio Cimadamore]

Hi,
i case you missed the commits, support for local variable type inference 
has been pushed in the amber repo (branch name is 'lvti'). The support 
is an updated version of the compiler patch that was shared some time 
ago [1, 2].

The prototype should be in a pretty mature stage, and it tracks the 
corresponding spec draft [4] pretty closely. That said, there are still 
some tweaks we'd like to do (some of them pending on the results of some 
spec discussions):

* share logic for upwards projection between javac and jshell
* refine handling of non-denotable types (esp. interesection types and 
anonymous class types) - see [3]

[1] - 
http://mail.openjdk.java.net/pipermail/platform-jep-discuss/2016-March/000038.html
[2] - 
http://mail.openjdk.java.net/pipermail/platform-jep-discuss/2016-March/000057.html
[3] - 
http://mail.openjdk.java.net/pipermail/amber-spec-experts/2017-March/000022.html
[4] - 
http://mail.openjdk.java.net/pipermail/amber-spec-experts/2017-March/000015.html