Address CRAN check issues

[coatless]

https://cran.r-project.org/web/checks/check_results_msos.html

Fix description:

Version: 1.0.1
Check: DESCRIPTION meta-information
Result: NOTE
Malformed Description field: should contain one or more complete sentences.
Flavors: r-devel-linux-x86_64-debian-clang, r-devel-linux-x86_64-debian-gcc, r-devel-windows-ix86+x86_64, r-patched-linux-x86_64, r-patched-solaris-sparc, r-patched-solaris-x86, r-release-linux-x86_64, r-release-windows-ix86+x86_64, r-release-osx-x86_64, r-oldrel-windows-ix86+x86_64, r-oldrel-osx-x86_64

Address Base R's switch to importing functions:

Version: 1.0.1
Check: R code for possible problems
Result: NOTE
bothsidesmodel: no visible global function definition for ‘lm’
bothsidesmodel.chisquare: no visible global function definition for
‘pchisq’
bothsidesmodel.hotelling: no visible global function definition for
‘pf’
bothsidesmodel.hotelling: no visible global function definition for
‘pchisq’
bothsidesmodel.lrt: no visible global function definition for ‘pchisq’
bsm.fit: no visible global function definition for ‘lm’
bsm.fit: no visible global function definition for ‘cov’
lda: no visible global function definition for ‘var’
negent3D: no visible global function definition for ‘runif’
negent3D: no visible global function definition for ‘optim’
qda: no visible global function definition for ‘var’
Undefined global functions or variables:
cov lm optim pchisq pf runif var
Consider adding
importFrom("stats", "cov", "lm", "optim", "pchisq", "pf", "runif",
"var")
to your NAMESPACE file.
Flavors: r-devel-linux-x86_64-debian-clang, r-devel-linux-x86_64-debian-gcc, r-devel-windows-ix86+x86_64, r-patched-linux-x86_64, r-patched-solaris-sparc, r-patched-solaris-x86, r-release-linux-x86_64, r-release-windows-ix86+x86_64, r-release-osx-x86_64, r-oldrel-windows-ix86+x86_64, r-oldrel-osx-x86_64