ENH: condition number for matrix exponential
MAINT: comment wording
TST: add a condition number test for a matrix that is badly conditioned with respect to expm
TST: expm condition number 1x1 tests
MAINT: use minimize() instead of fmin* and document the norm in which the condition number is computed
DOC: clarify that expm_cond computes the relative condition number as opposed to the absolute condition number
TST: finish converting the slow test from fmin_* to minimize
Merge pull request #3140 from argriffing/expm-frechet-kronform

ENH: linalg: condition number for matrix exponential