read.mpcross: Construct mpcross objects from datafiles
In mpMap: Multi-parent RIL genetic analysis

Generate an mpcross object by reading in components from files - requires founders marker data, finals marker data, pedigree, and IDs for all lines. Marker map and phenotypic data are optional.

1 2	read.mpcross(founderfile, finalfile, pedfile, mapfile, phenofile)

`founderfile`	File containing founder genotypes - should have 1+(number of founders) columns. The first column contains the marker names - first space left blank. The first row for the other columns contains the founder name. Additional rows contain observed marker data for all founders.
`finalfile`	File containing final genotypes - should have 1+(number of lines) columns. The first column contains the marker names - first space left blank. The first row for the other columns contains line names. Additional rows contain observed marker data for all lines.
`pedfile`	File containing pedigree data - should have three or four columns - first three columns indicate id, mother and father; fourth column is a flag for whether the lines was observed.
`mapfile`	File containing linkage map - should contain three columns - one for marker names, one for chromosome assignment and one for map position in cM
`phenofile`	File containing phenotypic data - should contain one column for each phenotype, with rows indexing lines.