Miscellaneous fixes

Miscellaneous fixes
- Splitting the two instances of CheckArgument. The template version is now always defined in base/exception.h and is available in a cvc4_public header. This version has lost its variadic version (due to swig not supporting va_list's). The CPP macro version has been renamed PrettyCheckArgument. (Taking suggestions for a better name.) This is now only defined in base/cvc4_assert.h. Only use this in cvc4_private headers and in .cpp files that can use cvc4_private headers. To use a variadic version of CheckArguments, outside of this scope, you need to duplicate this macro locally. See cvc3_compat.cpp for an example.
- Making fitsSignedInt() and fitsUnsignedInt() work more robustly for CLN on 32 bit systems.
- Refactoring ArrayStoreAll to avoid potential problems with circular header inclusions.
- Changing some headers to use iosfwd when possible.