Fixed a test issue where net45 methods were used in net40 profile
[runtime]Add a wrapper around signal handlers to ease porting work.
Correct VFP detection in mono-hwcap-arm.

This is supposed to be the value 64, not 100.
Enable GCC atomics on sparc32/64.
Remove dead s390(x) code from mono-membar.h.
Merge pull request #790 from akoeplinger/fixtests

Fixed a test issue where net45 methods were used in net40 profile