Made glfwGetWindowSize immediate.

Conflicts:
	src/internal.h
Removed glfwGetScrollOffset.

Scroll events do not represent an absolute state, but rather an interpretation
of a relative change in state, like character input.  So, like character input,
there is no sane 'current state' to return.  The here removed solution, that of
accumulating an offset since the last call to event processing, is at best
mildly confusing.  If a user wishes to implement this solution, it is better for
it to be explicit in client code than implicit in GLFW calls.
Re-used POSITION_* tokens for monitor position.
Documentation work.
Made glfwGetGammaRamp act directly.
Moved function into correct category.
Replaced glfwGetMonitorParam with glfwGetMonitor*.

Having one way to retrieve the cursor position and another (more
verbose) way to retrieve the monitor position is inconsistent.  Having
them both work the same way is the least surprising thing.

The expected glfwGetMonitorSize function gets an added Physical in its
name so users won't confuse it with glfwGetVideoMode.
Reintroduced glfwGetWindowPos, glfwSetWindowPos.
Documentation formatting.
Fixed Windows GLFW library names.
Simplified function comment headers.
Only disable tests and examples if not using OpenGL.
Removed installation of readme.