More DirichletBoundary constructors

Not requiring pointers makes it easier to use temporaries as the
FunctionBase arguments
Read the number of global variables present in the Exodus file when
we read the header, and don't try to initialize the global variables
if there are already some global variables present.
Revert "Adding _timestep_offset to hopefully avoid overwriting data when appending."

This reverts commit f7a552fb0c97eeba57a01fac1edbbb62a71e33d2.

We eventually decided that, since we sometimes *do* actually want to
overwrite prior solutions when appending, we must leave the timestep
to be written completely under the user's control.  This means more
flexibility, but more potential for accidental overwriting.
Handling "blank" entity names in XDA format
Removing debugging statement...
Adding Kirk, 2013c.
Removing dead links.
Removing outdated preprints.
Bug fix - Reading unique IDs from XDA/XDR should be determined by what's encoded in the file, not how libmesh is configured
Fixing ifdefs.
Adding ExodusII_IO::get_num_time_steps() interface.

Unify code for reading the number of timesteps in an Exodus file.
Avoid reinitializing element variables when appending to Exodus files.
Move FEMap constructor to C file, use default constructors
for std::vectors.
Fix up minor formatting issues.
minimum expected update required for intel-14.
Add configure option to enable/disable library warnings.
Result of running bootstrap after new --enable-warnings option added
Merge pull request #161 from permcody/enablewarnings

libmesh warnings
Also read the block information when appending.
Updating XDR interface to be compatible with OSX 10.9.