Reintroduced copy error button.

Revert "Reverted 'copy error' button for 1.0.5, waiting for a better UI design"

This reverts commit cf4584eb29c45c96ced13d11ff6a09005d225d17.
Fixes #1432
keywords syntax highlighting corrected in SoftwareSerial library
Fixed #1426
Merge branch 'master' of https://github.com/arduino/Arduino