UI Label and description consistency

I'm **slightly nervous** about suggesting these changes  - but some labels/description do seem inconsistent at the minute. It would look like this. See what you think, anyway.
![ui-tc1](https://f.cloud.github.com/assets/5730290/1461136/67fba80c-4496-11e3-9aed-c5efe92d2544.png)

**Details...**
'Tests' replaces 'Conditional Operators' in Draw label
'test' replaces 'condition' in Block labels and descriptions
Add 'commands' label to looping blocks
Disambiguate Repeat Blocks
delay micros/millis Typo and description improved
Tiny Typo in exception message.

**Reasoning. Dragged back from a previous issue**
"Why 'test'? I’ll largely be using this with students who have not programed before and I’m concerned they will find the block titles and labels confusing.

For example, ‘if’ statements have ‘tests’ – loops have ‘conditions’ and we find those in a draw marked ‘logical operators’. In normal speech it’s clear that a test is Pass or Fail / Right or Wrong / True or False. The meaning of ‘Condition’ in everyday speech is less clear.

Label ‘test’ and a draw marked ‘Tests’ would be better for me. I understand people aren’t just using ardublocks with beginners though - and they will understand things how they are now."