Add mono/metadata/mono-route.c for non-Linux ParseRouteInfo_local

Add mono/metadata/mono-route.c for non-Linux ParseRouteInfo_local

Add #ifdef to ignore code in mono/metadata/mono-route.c if OS=linux
Also remove mono-route.c from msvc/libmonoruntime.vcxproj (Windows)

Add #ifdef to ensure mono/metadata/mono-route.h code is not included
on Linux

Change to using #if defined(PLATFORM_MACOSX) || defined(PLATFORM_BSD)

Use sizeof(addr) for maximum length of IP address string, instead of the hard-coded 16.
Should the size of addr ever change it will keep us from disaster in case if shrinking the array length.
Also, do not ignore snprintf return value - check for truncated output and act accordingly if it happens.

Add Tests for System.Net.NetworkInformation/IPInterfacePropertiesTest.cs and System.Net.NetworkInformation/NetworkInterfaceTest.cs

Remove accidental Copyright

add a space before the opening parenthesis, as shown in the coding guidelines.

Indent TestFixture to align with coding style of newer Test classes

Use G_N_ELEMENTS(mib) instead of sizeof(mib) / sizeof(mib[0])