Driver-controlled circuit breaker

Add the possibility for a driver to control the circuit breaker of the locomotive(s).

Discussion: http://www.elvastower.com/forums/index.php?/topic/28645-circuit-breaker-for-electric-locomotives/
Roadmap: https://trello.com/c/I1zY1HZn/186-driver-controlled-circuit-breaker

How does it work ?
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Default circuit breakers :
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There is 2 default circuit breakers included in OR : the automatic one and the manual one.
The automatic one works as before. The manual one can be control by the driver.

ENG file parameter :
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The automatic circuit breaker is selected by default.
In order to select the default manual circuit breaker, write this parameter in the Engine section :
ORTSCircuitBreaker( Manual )
You can also put the name of a script file in this parameter :
ORTSCircuitBreaker( SNCFCircuitBreaker.cs )
(the script above is now available on my Github repository)

The file must be located in the SCRIPT directory of the locomotive.

The ORTSCircuitBreakerClosingDelay can be used to delay the closing of the circuit breaker.
For example, the delay is near 2 seconds on a French train :
ORTSCircuitBreakerClosingDelay( 2s )

Key assignments :
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2 new key assignments are available :
- O for a circuit breaker closing order button or switch
- I for a circuit breaker opening order button
- Shift + O for a circuit breaker closing authorization (not used in the default circuit breakers)

A combination of those can be defined in the scripts.

For example, the default manual circuit breaker uses only the O key while the SNCF circuit breaker uses the O and Shift+O key.

CabView controls :
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8 new cabview controls are available.

3 controls can be used by the driver (by mouse or keyboard) :
- ORTS_CIRCUIT_BREAKER_DRIVER_CLOSING_ORDER
- ORTS_CIRCUIT_BREAKER_DRIVER_OPENING_ORDER
- ORTS_CIRCUIT_BREAKER_DRIVER_CLOSING_AUTHORIZATION
The style of these controls must be set to PRESSED, WHILE_PRESSED or ONOFF.
For example, on SNCF locomotives, the closing order is set on PRESSED and the closing authorization is set to ONOFF.

5 controls can be used as state display :
- ORTS_CIRCUIT_BREAKER_STATE (0 = open, 1 = closing, 2 = closed)
- ORTS_CIRCUIT_BREAKER_CLOSED (0 = open / closing, 1 = closed)
- ORTS_CIRCUIT_BREAKER_OPEN (1 = open / closing, 0 = closed)
- ORTS_CIRCUIT_BREAKER_AUTHORIZED (TCS + driver authorization + other conditions such as pantograph up, etc.)
- ORTS_CIRCUIT_BREAKER_OPEN_AND_AUTHORIZED (used in order to tell the driver that he can trigger a closing order)

Sound triggers :
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9 sound triggers are available :
- 150 : Circuit breaker open
- 151 : Circuit breaker closing
- 152 : Circuit breaker closed
- 153 : Circuit breaker closing order on
- 154 : Circuit breaker closing order off
- 155 : Circuit breaker opening order on
- 156 : Circuit breaker opening order off
- 157 : Circuit breaker closing authorization on
- 158 : Circuit breaker closing authorization off