Fine grained TR1 header and namespace check.

This is aimed and fixing the build errors on OS X Mavericks, but
improves tr1 handling on every platform.
Use US prefix in feature macros.
Fixed handling of build-in library version and updated version tests.
Fixed memory leak due to non-virtual destructor.
Build the development branch with Travis.
Merge branch '7-check-for-tr1-includes-and-namespaces' into development

* 7-check-for-tr1-includes-and-namespaces:
  Use US prefix in feature macros.
  Fine grained TR1 header and namespace check.
Merge branch '8-service-listener-memory-leak' into development

* 8-service-listener-memory-leak:
  Fixed memory leak due to non-virtual destructor.
Merge branch '10-version-number-manifest' into development

* 10-version-number-manifest:
  Fixed handling of build-in library version and updated version tests.
Build release branches with Travis.
Updated tested compiler versions and platforms.
Bumped version number to 2.1.0.
Merge branch 'release-2.1.0'