Explain that the servo board needs 12V to work

As with the motor board, the servo board does not operate correctly if
the power side of the board is unpowered. Point this out to teams, and
by identifying the 5V-rail-on LED, give them means to debug this
problem.

Change-Id: Ifd8287ae2ad1b41669820a6a9eddca5ad3fd84f9
Update to Revision 2 of the rulebook

This is based on a build of rules.git at a5db35f.
Remove Inkscape extensions from power output labels
Draw a diagram of the V4 servo board

Stark yes, but also useful. There's not a lot on the board.

Matters such as what 'Auxillary' and 'UART' mean should be explained on
the doc page, of course.

Change-Id: I8d0aca16a2a91986232ed7e589733d102397e3a6
Add Bristol tech day 1
Add polarity signs to the power board diagram

While these are also on the board case itself thanks to the sticker
(from which these are taken), it's still nice to have the complete
information in the docs.

Patch Set #2: Unflow text and Inkscape gunk for standards compliance
Patch Set #3: Reduce some patch churn

Change-Id: I6fd3f42d689b570b06f74edc19252a9c74d6de12
Round the corners of the power board diagram

This matches reality and makes the diagram look less stark.

Patch Set #2: Rebased

Change-Id: I2b58ed9eba25b38e10f43f6fb7293771bce91743
Add the Power Board diagram to its page

This exports the svg to a png and includes that in the page.

Change-Id: I9af5f7cb90628eb25e0fc00ce9b65d264dcec7a1
Mention the start and On|Off buttons at the top

Even with the diagram, this clarifies that these are on this board.

Change-Id: Iabde04f7329d41979d732c939bcf8c64b9921e01