Maximum number of database lines

[matt]

Currently the maximum number of lines that the database can hold is set to a constant value and stored in the variable MAX_NUM_LINES and defined in taulines.h.

The addition of Kurucz lines into the Chianti data files has caused this limit to be exceeded.

This maximum value should be determined by what is needed rather than a fixed value. This means that Cloudy should figure out how many lines need to go in the database and then set MAX_NUM_LINES to that value.