Documentation for version 1.0

Final updates to readme.md and change-log.md for ARM Trusted
Firmware version 1.0. Also increment the version in the Makefile.

Change-Id: I00fe1016c8b936834bbf7bbba7aab07f51261bbb
Merge pull request #205 from danh-arm/dh/1.0-docs

Documentation for version 1.0