Release 1.23.2.1, coot dependency code included, bug fixes

Written for mmdb by Morten Kjeldgaard on 2010-12-15

There are some significant recent changes on the MMDB code. All patches from the Coot dependencies distribution (1.23.2) have now been merged into the project code base, and the code was released as version 1.23.2.1. In addition, there are some quite significant bug-fixes. Most are latent bugs, where variables are initialized inside a conditional statement, but referenced outside. These bugs will hit only if the conditional is not fullfilled (which may be never). The typical fix is to set these variables to zero, the code might still be buggy, but at least it will fail in a predictable way. The most serious bug, that would prevent the rwbrook Fortran bindings from ever dealing with atomic displacement tensors in fractional form, is fixed in this release.