Change-Id: I51db0511c52c79f2b322a1fdef798b061941887b

Change-Id: Ie2965f48810bf24cccf098b69a9d471583efc3bf

Adding an API reference for the supported languages.

General docs cleanup, including a new `tutorial` section that
supports all of the supported languages.

Added samples for each supported language to mirror the new
tutorial page.

Cleaned up all the links by making them `@ref` style links,
instead of referencing the names of the generated `.html` files.

Removed all generated files that were unnecessarily committed.

Also fixed the C# tests (two were failing due to a missing file).

Bug: b/25801305

Tested: Tested all samples on Ubuntu, Mac, and Android. Docs were
generated using doxygen and viewed on Chrome.

Change-Id: I2acaba6e332a15ae2deff5f26a4a25da7bd2c954

Change-Id: I6e9e66c3d7d67c54617bc892f612b7341bebd7e0

Change-Id: Ia6b976f0eb6a99d710bcd09cb56339580ff69f5b

Change-Id: I140e1322fc1bfb3ab8012e00d8f3006ee2e7ce95

This is such that if you mis-spell an attribute, it doesn't get
silently ignored.

Bug: 18294628
Change-Id: I10013f5b2a21048b7daba2e9410678f528e09761
Tested: on Linux.

Bug: 15521443
Change-Id: I2e1ef97e7225a1a0ecf2ca65e31d49d443003747
Tested: on Linux.

Change-Id: I4c9f0f722490b374257adb3fec63e44ae93da920
Tested: using VS2010 / Xcode / gcc on Linux.