Update installation.rst

Add comment about making changes in ``app/config/config.yml`` if you want to use other than SQLite database driver. That information was missing and it was impossible to set database without knowing that.
Update introduction.rst

Variable name in code snippet is wrong
Update create_your_own_blocks.rst

Missing code in snippet
Merge pull request #509 from gonzalovilaseca/master

Update create_your_own_blocks.rst
Merge pull request #508 from gonzalovilaseca/patch-1

Update introduction.rst
Show new cache adapters names

In order to find the cache adapters introduced by CMF block bundle one has to dig into the code, it would be very useful to have them in the documentation.
Update cache.rst
Merge pull request #497 from sosek108/master

Update installation.rst
[#497] Minor fixes
Merge pull request #510 from gonzalovilaseca/patch-2

Show new cache adapters names
[#510] Minor fixes
[FIX] Typo
Merge pull request #512 from Th3Mouk/patch-1

[FIX] Typo
Fixed #513
Merge pull request #516 from phiamo/extension_doc

Updated extension documentation
add note about blog bundle being in development
Fixed typo on code example

The $page document should be in /cms/simple/ section, not /cms/routes/
Merge pull request #518 from eiannone/patch-1

Fixed typo on code example
Merge pull request #517 from symfony-cmf/note-on-blog-bundle

add note about blog bundle being in development
add note about blog bundle being in development