Improved tex

This pull request makes docmake’s latex generation more robust and general.

1. Insertion of references is added, with new notation in network file.

2. User defined mapping of variables to latex symbols in latex options (json) file.

3. Optional deferred resolution of selected variables to list below the reaction table to simplify very complicated rate expressions.

4. More robust cleanup of latex expressions and line breaks in equations

Note: Adds dependency on non-standard module regex

• RAMSESTH Fix typo in debug dump

• DOCMAKE (latex) fixed reaction order and added reference syntax

• LATEX dexp -> exp and fix numbering of coeficients

• DOCMAKE (latex) Aligned rate equations and temperature ranges

• DOCMAKE (latex) Print large temperature limits in scientific notation

• DOCMAKE (latex) More robust variable substitution ("shortcuts")

• DOCMAKE (latex) Symbols and robust line breaks in equations

  Note: This commit adds an external dependency: the regex module

• DOCMAKE (latex) Defer resolution of some variables in complex expressions

  They are printed as latex symbols in the reaction table, and are listed with their resolved expressions in a separate table.

• DOCMAKE (latex) moved substitution and symbol lists to options file

• DOCMAKE (latex) both horisontal and vertical alignment of rates

  ...almost

• DOCMAKE (latex) convert long fractions to use / sign

• DOCMAKE (latex) handle no references right

• DOCMAKE (latex) fixes + automatic formatting of number densities and species in rate equations

• DOCMAKE (latex) updated options and template

• DOCMAKE (latex) added options, template, bib for CO_rt network