Merge pull request #2994 from ludovic-henry/remove-nacl

[runtime] Remove support for NaCl

diff --cc configure.ac
Simple merge

diff --cc mono/metadata/domain-internals.h
Simple merge

diff --cc mono/mini/exceptions-arm.c
Simple merge

diff --cc mono/mini/mini-runtime.c
Simple merge

diff --cc mono/mini/mini.c
Simple merge

diff --cc mono/mini/mini.h
Simple merge