We'll start with version 0.90.0 and increment the second number up to 99.
  Goal is to declare a verison 1.0.0 sometime over the summer.

  To change the version, edit both SConscript.py and Makefile.

  Eliminate duplicated/redundant configuration code in SCons system
  Let SCons also clean ROOT 6's *_rdict.pcm class layout cache files
  Move helper python script to site_scons
  Remove EVIO from scons as podd build will take care of it.
  Remove define of HALLC_MODS in SConstruct
    (There is no longer any Hall C conditional code in Podd)

Modify SConstruct to prepend $ROOTSYS/bin to PATH, rather and append, so that SCons will use the most recently defined user-installed version of ROOT, or the system version, if no user version exists.

Also, make ROOT environment definition consistent with Podd.

  Fixes building when using scons 3.0 which apparenlyt uses python3.
  Fixes broken building on travis

autogeneration of src/HallC_LinkDef.h - all using SCons

As it turns out, this was not so easy fix. I had to do:
- add at least c++0x support to scons (works for g++ 4.4.7!)
- change how my DefineVariables works

The c++0x support is bonus, since now we can use some additional features, like auto keyword (see https://gcc.gnu.org/gcc-4.4/cxx0x_status.html).

  evio .so now gets copied to top of podd directory

Copy evio into podd directory

  Fixed for make and scons
  Put libHallC before libHallA before root libs

Podd no longer has the hana_scaler directory.

Also, on the advice of Stephen Wood, remove references to INSTALL_DIR (evio)
and now only check for EVIO_LIBDIR and EVIO_BINDIR.  Also, suppress
compilation of the evio libraries (as those directories may not be world
writeable.  So, the assumption now is that local installations of the
evio libraries will be done correctly (by the local user or the local
system administrator).

JLab, if it does not exist locally already.

SConstruct