gcc: update to support compressed debug sections

Add a static build of zlib (1.2.8) required to support compressed debug
sections. Use static zlib for elfutils, binutils, and gcc.

Drop CXX and CXXCPP from elfutils, it's written only in C.

Add new options for GCC:
--enable-__cxa_atexit
--disable-libunwind-exceptions
--enable-gnu-unique-object
--enable-plugin
--with-linker-hash-style=gnu
--enable-linker-build-id
--disable-dssi

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
gcc: fix $PATH; use 'eu-' program prefix for elfutils binaries

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Configure cmssw-validation to use das-cache file.
Merge pull request #416 from ktf/check-das

Configure cmssw-validation to use das-cache file.
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Misc cleanups.

- Use das-cache for runTheMatrix.
- Point to git based int-build scripts.
- Drop commented code.
Merge pull request #418 from ktf/test-das-cache

Use das-cache for runTheMatrix.
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Update scripts every minute.
Merge pull request #449 from ktf/update-hourly

Update scripts every minute.
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable