Julia support

Hi,

It will be awesome if renovatebot, could parse Project.toml in Julia Project.

Dependencies in julia could be specified in various ways :

• ^1.2.3 => [1.2.3, 2.0.0)
• ^1.2 => [1.2.0, 2.0.0)
• ^1 => [1.0.0, 2.0.0)
• ^0.2.3 => [0.2.3, 0.3.0)
• ^0.0.3 => [0.0.3, 0.0.4)
• ^0.0 => [0.0.0, 0.1.0)
• ^0 => [0.0.0, 1.0.0)
• ~1.2.3 => [1.2.3, 1.3.0)
• ~1.2 => [1.2.0, 1.3.0)
• ~1 => [1.0.0, 2.0.0)
• ~0.2.3 => [0.2.3, 0.3.0)
• ~0.0.3 => [0.0.3, 0.0.4)
• ~0.0 => [0.0.0, 0.1.0)
• ~0 => [0.0.0, 1.0.0)
• >= 1.2.3 => [1.2.3, ∞)
• ≥ 1.2.3 => [1.2.3, ∞)
• = 1.2.3 => [1.2.3, 1.2.3]
• < 1.2.3 => [0.0.0, 1.2.2]

@codeneomatrix Do I forget anything according julia and deps management

@rarkins You can find a example in https://github.com/the-benchmarker/web-frameworks/blob/e2c82e935f9038fe7a54a10d04654b31eacf8ee8/julia/merly/Project.toml#L4

Regards,