Merge pull request #1 from lcolladotor/master

Minor change to readGown
Documented the package
export functions
updated gitignore
formatting cleanup
formatting cleanup (II)
fixes exon order in creating transcrip structure object
adds methods for accessing phenotype & expression data quickly
exports pData, texpr, eexpr, and iexpr methods
fixes formatting; adds extra defense about features/measurements
adds f.pvalue function from sva to ballgown package
implements intial version of timecourse stat test (UNTESTED FUNCTION)
fixes package imports
adds checkAssembledTx to collate (forgot before)
adds missing paren
fixes exon ordering (bug fix from months ago)
imports only join_all from plyr
removes unnecessary library calls from ballgown constructor
adds possibility of passing pData directly as dataframe
adds R CMD BATCH extraneous files to gitignore