Packaged function objects: added a Description entry

etc/caseDicts/postProcessing/faceSource/patchAverage

etc/caseDicts/postProcessing/faceSource/patchIntegrate

etc/caseDicts/postProcessing/fields/CourantNo

etc/caseDicts/postProcessing/fields/Lambda2

etc/caseDicts/postProcessing/fields/MachNo

etc/caseDicts/postProcessing/fields/PecletNo

etc/caseDicts/postProcessing/fields/Q

etc/caseDicts/postProcessing/fields/R

etc/caseDicts/postProcessing/fields/components

etc/caseDicts/postProcessing/fields/div

etc/caseDicts/postProcessing/fields/enstrophy

etc/caseDicts/postProcessing/fields/flowType

etc/caseDicts/postProcessing/fields/grad

etc/caseDicts/postProcessing/fields/mag

etc/caseDicts/postProcessing/fields/magSqr

etc/caseDicts/postProcessing/fields/randomise

etc/caseDicts/postProcessing/fields/turbulenceFields

etc/caseDicts/postProcessing/fields/vorticity

etc/caseDicts/postProcessing/fields/wallShearStress

etc/caseDicts/postProcessing/fields/writeObjects