This is done with a loop that iteratively creates array 'x' by starting
at zero and continuing until gradient is hit, at which point the mesh
starts becoming finer and then coarser again.

Whether or not two meshes agree well numerically seems to depend on
how well connected two differently spaced mesh domains are.

This reverts commit 93f115a6.

Droplet can now have different size than one and still start at zero. 
Other minor changes prior to changing units.

MAJOR BUG FIXED. x domain now starts at zero. pdepe enforces no-flux for spherical coordinates at absolute zero, not at the beginning of the domain.

Adding peaked initial conditions to ternary FRAP. Also adding figure comparing time course with steady state.

Matlab code for ternary model for unbleached molecules seems to work properly now. Problem before: volume fraction not defined properly and thus low mobility inside.