Fix typos thanks to Léa Paulus - meca q2
Change indenting - meca q2
convergence to divergence - math q1

Thanks to Sofyan Ventura
Fix typo thanks to David Steinmetz - eco q4
Change C_F condition - eco q4

On a $C_F$ même si $q = 0$
Fix uncertainty with sampling scaling - sigsys q4

I was not sure why it was not 2pi/T_s but 1/T_s but
it's due to the 1/2pi factor
Merge branch 'master' of github.com:Gp2mv3/Syntheses