New version for ultipack.sty. mathoper.tex: added a operator for the rectangular window
Added a biblatex file (phd_refs.bib) with some references
ultipack.sty: replaced fixme package by todonotes
mathoper.tex: starred version of newcommand, added upright imaginary, Euler and derivative symbols, added operators for expectation, variance and covariance, defined derivative, gradient, divergence and curl functions
ultipack.sty: uncommented biblatex package and modified its options, removed page symbol (p.) in the references file (not needed by biblatex)
Changed the references folder name to bib and deleted the refs folder
ultipack.sty: minor correction for biblatex option
Added a latexkrc file that sets the TEXINPUTS variable for the local project
Added a README file
Added a link to the bib folder in latexmkrc
ultipack.sty: added customizations for captions and subcaptions