Detect paths with illegal bridging offers
Ste version to 0.25.2-rc1
Revert "Ste version to 0.25.2-rc1"

This reverts commit 3f109245941979cf28c9627df97906f837b8fc38.
Make all include paths relative to a root directory:
* Better include path support in the VSProject scons tool.
* Various manual fixes to include paths.
Refactor MultiSocket:
* Variadic constructor argument list
* Tidy up sources and filenames
base_uint now compares and assigns with beast::Zero.

Conflicts:
	src/ripple/types/api/base_uint.h
	src/ripple_basics/ripple_basics.h
Add Dockerfile:
* The ports are not automatically exposed.
* No test is performed after the build.
Check for openSSL version in SConstruct.

* Uses the openssl binary to detect the current version.
* Also detects compilation platform, and makes a C++ definition for it:
  Ubuntu:  RIPPLE_UBUNTU
  Windows: RIPPLE_WINDOWS
  OS/X:    RIPPLE_DARWIN
  Debian:  RIPPLE_DEBIAN