Cosmetic changes into the CAPI code, by Mike Toews

 - Replace "reader" with "writer" in prototypes
 - describe "_r" functions
 - Function arguments with only one geometry changed from g1 to g
 - Rename nf -> ef for GEOSContext_setErrorHandler_rsetErrorHandler_r
 - Move GEOSBuffer* declaration to top of buffer related function section
 - Change char* mat to char *mat
 - Fix typos in comments
 - Clip trailing white space, and other white space consistencies
 - Other minor rearrangements for consistency

git-svn-id: http://svn.osgeo.org/geos/trunk@3848 5242fede-7e19-0410-aef8-94bd7d2200fb