Fixing shifting by number equal to the width of the type

Thanks to Stephen McCamant for advice.

Fixes #78
Removing declared but undefined function
Fixing typo sentinal -> sentinel
Adding #include so parsing is possible by IDE

It's actually needed, but everything that includes NodeIterator.h
already #include-s ASTNode.h
Fixing missing #include -- fixes IDE code parsing

This is needed, as we have a reference to it in the header. But
everything that includes this header already includes the STPManager.h
If vc_error_hdlr is undef we can drop off the end of a func w/o return

It is always defined as it looks right now, but GCC doesn't know this
and warns that it is possible to exit the function without having set a
return value. Putting an exit(-1) in case vc_error_hdlr is not defined
fixes this warning.
Update comment to reflect changes made in
3cf115b90975855323fb64bb492daaefc7fcb36f
Fixed overshift guard to be correct and more readable than
what was added in 3cf115b90975855323fb64bb492daaefc7fcb36f
Fixed mistake in f02f87c7fcd3c1e1328a9d9de14e0e5ea23b370c where
I was accidently comparing bits with bytes instead of bits with bits.
Renamed and improved the test formerly known as
getbvunsignedlonglong-check. One test is commented out
right as it seems to cause memory errors.
Enable getbv.INT32 test. I've worked around the bad C interface
design for now.
Update INSTALL

Added link to STP's testing documentation.
Add -fPIC flag if supported when building the abc library when
building libstp as a shared library.
Fix linking issues when building libstp as a shared library by removing
commenting out (eurgh...) dead code.

This is based on the work of Jurriaan Bremer

The abc code calls external functions

Abc_FrameGetGlobalFrame Abc_ShowFile Fra_FraigChoice Cmd_CommandExecute
Kit_SopFactor

which are not defined anywhere which causes problems when trying to link
By removing all functions that call these external functions, and then
removing functions that call the functions we just removed and so on...

we prevent compilation of dead code that causes linking errors.

We should really just remove this library altogether and try and use the
upstream abc library.
Add CMake option ALSO_BUILD_STATIC_LIB to allow building libstp
statically at the same time as building the dynamic version.

Note that the stp executable will link against the dynamic version
of the library in this case.
Modify how targets are exported so now both the static and shared
library can be exposed to clients of STP

A user doing find_package(STP) can no longer use STP_LIBRARIES
because it has been removed. Instead this has been split into
two variables

- STP_STATIC_LIBRARY - static library target (empty if not built)
- STP_SHARED_LIBRARY - dynamic library target (empty if not built)

The simple example project has been modified to reflect this change.
Remove ALSO_BUILD_STATIC_LIB from the CACHE if it's value is no
longer used. This is for cmake-gui and ccmake users.
Teach travis to build libstp as a dynamic library and as a static
library.
Merge pull request #94 from delcypher/fix_sharedlib

Fix shared libraries
Set BUILD_SHARED_LIBS to ON by default. The ALSO_BUILD_STATIC_LIB
is set to on by default so clients who expect a static library
(which is almost everyone because support for building a shared
library was only added recently) still have it available by default.