add command line option -mpqc3 to pt2r12 program, it's used to control if use MPQC3 new feature, the default is false.
MPQC3 new feature in pt2r12 only works if MPQC is compiled with TA
change -mpqc3 command line option only available for MPQC3, and the default value is true
LMP2 print out occupied pair data: energy, distance, etc.
Fixed bug which where faulty assumption was made about first shell in a tiledbasisset.
Added --ldflags option to mpqc-config
Update compute_density_diag.cc

Closes #17
Fixed a CMAKE bug which compiled lbfgs.f, lbfgs.f was included in source for documentation purposes only and should not be compiled.
Merge pull request #15 from pchong90/master

command line option -mpqc3 in pt2r12 program
Fix for boost with clang 3.4 just replace bad files with correct versions.
Fixed cmake code related to boost patch for apple clang
Fixed SpinOrbitalPT2R12
MPQC_ASSERT as the only clause of if/else must be in brackets now.
Minor documentation updates.
CoreIntsEngine can take optional precision param
Factored out default grid construction for Molecule
Fixed problem with generation of gaussian cube files with orbital grids.
Changed default grid file name to basename.grid
Disable new CI code by default.
Added Mg and Zn to cc-pVDZ and added a TODO file to the main directory which intends to mirror Elemental's TODO.
Merge branch 'master' of https://github.com/ValeevGroup/mpqc