adding exception class for failed diagonalization
Fix a typo in documentation of fs_svd()
Fix reordering of singular vectors of a non-square matrix

so that in the SVD, m == u * sigma * vh, sigma(i,j) == 0 if i != j.
Generalize documentation of SVD to rectangular matrices
Add diagonalization procedures that estimate error bounds
test/test_linalg2.cpp: fix typos
src/linalg2.hpp: include a missing header
add flags for imprecise mass eigenvalues
add configure switch to enable the eigenvalue error checks
print eigenvalue imprecision warnings to SLHA block SPINFO entry 3
remove trailing ; after function implementation definition
add helper function that allows shorter generated code
check SVD eigenvalue errors in tree-level masses
merge bad mass flag functions and generalize flag_tachyon function
check diagonalization eigenvalue errors in tree-level masses
put call of diagonalization functions into separate function

for later reuse in LoopMasses.m
simplify generated code for tachyon check
eigenvalue error check on loop masses as well
consistent naming of CHECK_* preprocessor defines
add missing header inclusion