Add new maps

 FIxes #73 

Map overviews:
- **card** - A complex square map, with 6 different sections
![card](https://f.cloud.github.com/assets/2147958/1895076/2e811e7c-7b0f-11e3-938f-b462f47edfb9.png)

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- **castle** - A map with a fort at the center
![castle](https://f.cloud.github.com/assets/2147958/1895075/2c7d3138-7b0f-11e3-8dc4-f69b945ca633.png)

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- **fourcorners** - A map with four corners, with bots spawning in each of them
![fourcorners](https://f.cloud.github.com/assets/2147958/1895074/2a8f1558-7b0f-11e3-9baf-ae2ed1098fe0.png)

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- **hourglass** - A hourglass shaped map, with a chokepoint at the center
![hourglass](https://f.cloud.github.com/assets/2147958/1895086/aa12e6be-7b10-11e3-8268-29d8260de723.png)

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- **mansion** - A complex map of a house with hallways and rooms. This is generally not suitable for most existing bots. Perhaps add a new league?
![mansion](https://f.cloud.github.com/assets/2147958/1895072/28143628-7b0f-11e3-82eb-a1d39d94db54.png)

***

- **metasquares** - A complex map, with many squares inside of other squares
![metasquares](https://f.cloud.github.com/assets/2147958/1895071/24da5f5a-7b0f-11e3-96c5-33868df9733a.png)

***

- **square** - A simple, square-shaped map
![square](https://f.cloud.github.com/assets/2147958/1895068/11e61fb0-7b0f-11e3-9e7d-1dd84dd3cba7.png)