*) Eddington approximation
*) Traditional approximation
*) Fix GL4 and GL6 cases for non-adiabatic
*) Read AMDL files [done]
*) Merge Magnus into single integrator
*) Newton-Coates integrators (better accuracy at boundaries?) [done; not worth]
*) Frequencies in output filenames
*) Deferred eigenfunction calculation
   - find all efreqs first, then find & write eigenfuncs one-by-one
     - no n info when calculating
   - find efreqs & efuncs, but throw away full efunc and store just n;
     recon efuncs when writing
   - find efreqs one by one, calc & write efunc when found
   [no longer needed; pruning]
*) Non-adiabatic function reconstruction
   - switch to algebraic reconstruction for y_5 and y_6 when a criterion is met
   - how calculate dy_6/dx when eval y_5? 
*) Move params around
   - reduce_order from num to osc
   - delete theta_ad [done]
*) Add real/imag versions of recon routines
   - do we really need a separate recon? Y not handled in mode?
*) Allow for inner boundary not at r=0
   - switch to modular/class based boundary conditions -- a separate class
     for each possible bc?
     - hmm, seems really unwieldy
     - unless we have internal classes provided by a factory module
*) Rename ext_real_t and ext_complex_t
   - r_ext_t, c_ext_t -- too opaque, but prefixes good
     -> r_spline_t, c_spline_t
     -> r_extfunc_t
     -> r_sysmtx_t
     -> in fact, I like it
   - xreal_t, xcomplex_t -- not badm but prefixes wrong
   - r_xarith_t - less opaque, but wordy

*) Modular boundary conditions
   - put, e.g., all ad bc's into single [done]





Resolved changes
----------------
*) Rename ext_real_t -> r_ext_t
*) Rename ext_complex_t -> c_ext_t
*) Create ext_t offering both r_ext_t and c_ext_t
*) Split ext_func -> r_extfunc and c_extfunc
*) Split sysmtx -> r_sysmtx_t and c_sysmtx_t
*) Tidy up codepaths in BVPs to handle different cases
*) How about r_bvp_t, c_bvp_t -- with standardized code paths?
   -- template classes! Sounds good
   -- but need shooters for modularization
   -- gyre_magnus_shoot, gyre_findiff_shoot etc.

