[WIP] Prepare for v1.0.0

[wildart]

Ready for v1.0.0 release

• [x] Provide a abstract supertype for multivariate analysis methods (#95)
• [x] Provide a simple interface for multivariate analysis methods
• [x] llsq: deprecate trans argument in favor of dims (#100)
• [ ] Abstract eigendecomposition to allow plug-in functionality (#119)
• [x] Do not export transform, and provide predict alias instead if relevant (#88)

[nalimilan]

Another thing to tackle is the fact that most methods treat columns as observations, except llsq (https://github.com/JuliaStats/MultivariateStats.jl/issues/38). Also that's inconsistent with cov, var, etc. in Statistics.

[wildart]

llsq has a argument trans which allows to switch between a column and a row representation of observations. I will deprecate it in favor of dims argument in order to standardize interface.

[gdkrmr]

how far is 1.0 away?