Attribute unmet INPUT dependencies to a DataLoader Algorithm

See merge request !269

See merge request !79

Closes GAUDI-1276

See merge request !267

fixes to CMake modules

Closes LBCORE-1304

See merge request !298

Closes LBCORE-1228

See merge request !289

gdb can be found in /usr/bin, in which case its directory must
not be prepended to the custom PATH

Search for heptools version only in target platform installs

Closes GAUDI-1280

See merge request !276

See merge request !275

see LBCORE-1304

minor fixes to exception reports in IncidentSvc

See merge request !291

do not require Gaudi::Property::ValueType to be default constructible

See merge request !271

See merge request !292

GaudiAlg::ID optimisation

See merge request !283

use std::showpoint instead of std::fixed to print numbers

See merge request !254

filter stdout for tests to hide removal of ErrorCounter property

See merge request !284

to enable debug symbols in optimized builds

The static ConcurrencyFlags allows easy access to information
about the number of threads, concurrent events, and processes.

For running in serial, numThreads == 0, numConcEvents == 0,
numProcs == 0, useful to distinguish between running serial,
and running MT with 1 thread, or MP with 1 process.

See merge request !277

a BINARY_TAG like x86_64-ubuntu1604-gcc54-opt+o3 will use -O3 instead of the
default (currently -O2)

platform detection and BINARY_TAG handling is done only
via BinaryTagUtils.cmake

- removed old heptools-##.cmake toolchains
- drop support for LCG toolchain info names never used
- remove obsolete treatment of AA projects platform

use BinaryTagUtils instead