make cmake honor PYTHON_LIBRARY
[FEATURE] allows to store SQL queries in the DB manager
Update to custom CRS management
Updates to compile with current master
check validity of CRS before saving
do not use QgsCoordinateReferenceSystem internally
Delimited text provider indexing implemented.

Efficiency improvements.

Adds capabilities
   SelectAtId
   CreateSpatialIndex

This uses line number as an index.  Allows jumping to a line number
without interpreting all intermediate records, so much more efficient.
Also retains the current record in a buffer, so successive requests for
the same record do not require rereading the file.

With index available have also added indexing of subsets and optional
creation of spatial index.

Note: did try using QTextStream.pos to build a random access index -
this was incredibly slow.  Have found using line based index is
reasonably fast even on quite large (50+Mb) text files.
Merge resolved
Merge branch 'customCRS' of https://github.com/leyan/Quantum-GIS
Merge branch 'master' into delimited_text_indexing_implemented
Minor fixes for better compatibility with KDevelop
Documentation fix
Merge pull request #582 from ccrook/delimited_text_indexing_implemented

Delimited text provider indexing efficiency improvements.
don't reload the whole browser model when the project home changes (fixes #7520)
allow credential requests from threads
oracle provider:
- make searching in meta data table default
- also list synonyms
- more progress messages
postgres provider:
- move available table detection to thread
- more progress messages
german translation update
Add rand and randf functions for generating random numbers
Small fixes to function help